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High-resolution virtual try-on with garment extraction using generative adversarial networks
No full textImage-based virtual try-on aims to depict an individual wearing a garment not originally worn by them. While existing literature predominantly focuses on garments from standalone images, this research addresses the use of images where the garment is already being worn by another individual. The study bridges a notable gap as most current systems are tailored for standalone garment images. The proposed system, given a pair of high-resolution images, extracts the garment from one, refines it using context-aware image inpainting, and subsequently transfers it onto the second image's subject. The methodology incorporates various off-the-shelf models, notably Part Grouping Network (PGN), Densepose, and OpenPose for pre-processing. A state-of-the-art context-aware inpainting model refines the garments, and the final synthesis leverages the HR-VITON architecture, producing images at a resolution of 768 × 1024. Distinctively, our model processes both standalone and garment-on-person images. Evaluating the models involves testing on 2 032 high-resolution images under both paired and unpaired conditions. Metrics such as RMSE, Peak Signal-to-Noise Ratio (PSNR), Learned Perceptual Image Patch Similarity (LPIPS), Structural Similarity (SSIM), Inception Score (IS), Fréchet Inception Distance (FID), and Kernel Inception Distance (KID) assessed the model's prowess. Benchmarked against HR-VITON, ACGPN, and CP-VTON, our model slightly trailed HR-VITON but notably surpassed ACGPN and CP-VTON. In realistic, unpaired conditions, the model achieved an IS of 3.152, an FID of 15.3, and a KID of 0.0063. This is compared to an IS of 3.398, an FID of 11.93, and a KID of 0.0034 achieved by HR-VITON on the same data. ACGPN has an FID of 43.29, and a KID of 0.0373, while CP-VTON has an FID of 43.28, while it has a KID of 0.0376. IS is not measured for both ACGPN and CP-VTON. An ablation study underscored the importance of context-aware inpainting in our network. The findings highlight the model's ability to generate convincing, high-resolution virtual try-on images from garment-on-person extractions, addressing a prevalent gap in the literature and offering tangible applications in high-resolution virtual try-on image generation
A design-based research perspective for multiple immersive digital conversations in academic research writing literacies
Get PDFIn the South African higher education context, academic writing support at the postgraduate level presents significant challenges for institutions. The conventional dyadic models of writing support, typically offered by writing centres, are increasingly viewed as inadequate in addressing the multifaceted nature of academic writing and literacy challenges. This study advocates for a shift towards a more inclusive and holistic approach, promoting trialogic and multi-lateral conversations within writing centres to address these challenges. The study's methodology is deeply rooted in literature and adopts Reeves' (2006) four-phase model to guide the Design-Based Research (DBR) approach. Through two iterative intervention cycles, the study integrates efforts from writing centres and subject lecturers to facilitate immersive conversations aimed at academic research literacy development. The third phase of DBR intensively focuses on testing and refining the interventions to address directly identified obstacles. The effectiveness of these interventions is measured through qualitative data collection methods, including surveys, interviews, observations, and document analysis. The study aims to answer the question: What are the design principles for facilitating multiple immersive digital conversations in academic research writing literacies? To answer this question, the study creates a dynamic and interactive environment where students can engage in meaningful dialogues and collaborative activities by integrating digital tools like Google Drive into the learning process. The study develops an integrated theoretical framework for multiple immersive digital conversations for academic research writing that interlinks linguistic, cognitive, and social elements. The study's participants include Bachelor Honours students and Advanced Diploma students, writing centre practitioners, and academic supervisors at a university in South Africa. The theoretical contribution of the study is a model of refined design principles for developing a robust intervention for multiple immersive digital conversations in academic research writing literacies. These principles advocate for pedagogies that respect and incorporate students' identities, aligning with adaptive and culturally inclusive teaching practices. In the realm of academic writing instruction, these principles have the potential to improve support systems significantly, enhancing students' academic achievements and advancing their research literacy skills
Lecturers' perceptions of enhancing student engagement through anonymous online engagement strategies
Get PDFStudent engagement is widely acknowledged as significantly impacting academic accomplishment and learning in higher education, and it is frequently theorised and researched. However, institutions of higher learning have historically grappled with effective and sustainable ways of engaging students online in the teaching and learning process. The COVID-19 pandemic, with its extensive lockdowns and instant shift to fully online teaching and learning, created a more challenging context for student engagement. During this time, faculties and departments shifted from face-to-face to online teaching to continue teaching and learning activities. The emergency remote teaching context impacted student engagement in a wide range of ways and created an opportunity to understand student engagement in different contexts. This dissertation seeks to explore lecturers' perceptions and experiences of student engagement in online learning, with a particular focus on anonymous engagement as a strategy to enhance student engage
Museum-worthy smartwatches: A medical humanities perspective
Get PDFThis thesis focuses on the relationships that bind people to their smartwatches along the Sea Point Promenade in the city of Cape Town. The study identifies smartwatches as objects with immense social, personal, and interpersonal traction. Materiality in anthropology is well explored and offers a range of theoretical tools for bridging the gap between human and machine as well as functional design and aesthetic. Research with ordinary smartwatch users invites inquiry into aspects of their use that directly affect health, well-being, illness detection and monitoring. Smartwatches are also branded and displayed in ways that signify class and aspirations. These aspirations are coded by their functional, symbolic, and artistic value. The research draws upon a comprehensive body of literature to contextualize and analyse how individuals utilize and perceive these devices, offering revitalized perspectives on smartwatches as machines that gesture towards ideas of convivial social relations. Conviviality puts the immediate in the larger context and the larger context in the immediate through deliberate connections, but also acknowledging the hierarchies and conflicting interests at play at the small and large scales of existence and consciousness. With a multimodal anthropological approach, the dissertation includes stories gathered over six months through ethnographic methods including participant observation, interviews, and the examination of public documents and artifacts. The research also explores audio reporting as a valuable tool for anthropology and ethnographic storytelling, providing insights into how people use, perceive, and experience smartwatches. The intriguing relationship between smartwatches and people's lived experiences in modern urban environments is explored as a way to contribute to the expanding conversation on the interplay between technology, health, and society. It emphasises the intricate relationship that shapes the contemporary healthcare landscape between technology innovation, societal norms, and individual autonomy through nuanced storytelling and critical analysis
Mapping the implementation of formal cross-border patient migration from Eswatini to South Africa through the Phalala Fund: an interpretive policy analysis
Get PDFThe rise of pandemics and epidemics underscores the global nature of health systems, transcending national boundaries across low- and middle-income countries (LMICs). This study delves into Eswatini's health system's challenges in implementing formal cross-border patient migration to South Africa through the Phalala Fund. This is a flexible qualitative study conducted in two phases. Evidence was gathered from primary, secondary, and grey literature to conduct a scoping review and an interpretive policy analysis (IPA) on cross-border patient migration and the Phalala Fund. Key stakeholders in implementing Phalala Fund's cross-border patient migration and their influence on the policy implementation process were identified. This was key in understanding the inter-subjective meanings shared across stakeholders. In implementing Phalala Fund's cross-border patient migration, stakeholders had varied systems of meaning shaped by their values and reality judgements. Thisinfluenced stakeholder actions, priorities, resource allocation strategies, and communication approaches, which have presented various challenges in implementing Phalala Fund's cross-border patient migration. Some challenges have further strained stakeholder relations, resulting in limited negotiation power of the Government of Eswatini with South African health providers. Although regional cooperation policy frameworks of the Southern African Development Community (SADC) were seen as necessary in shaping cross-border patient migration, they do not necessarily mirror the legal and regulatory provisions that address the specific changing needs in health migration. The findings echo the importance of longer-term strategising in implementing Phalala's cross-border patient migration and recognising the complexities and varied meanings across stakeholders. Policymakers in similar contexts should consider the existing stakeholder relations and use them to strengthen the implementation of cross border patient migration. Further areas of research on 'systems overlap' is suggeste
The impact of Enterprise Resource Planning (ERP) education in Zambia
Get PDFThis socio-technical study describes and explains the impact of an ERP course, introduced at the University of Zambia. Zambia lacks local ERP expertise required for the implementation and support of ERP systems in organisations. The research investigated the impact of this ERP education on the postgraduate students that went through the course and the resultant potential impact on organisations in Zambia. The research paradigm used to answer the research question was interpretivism and the research has three-parts. Study 1 used a deductive approach and Sen's Capability Approach to explain how student choices and personal, social, and environmental conversion factors impact student capabilities and functionings enabled by ERP education. The Zambian context which restricts higher salaries and employment prospects is evident. Study 2 inductively investigated the course outcomes of ERP education and the contextual factors that impact ERP education course outcomes. The impact of the teaching model and the course limitations on course outcomes were explained and a richer understanding and impact of the Zambian context, in which foreign expertise is preferred over local expertise is presented. Study 3 inductively investigated the ERP challenges experienced by organisations in Zambia and the potential impact of ERP education on organisations and on the outsourcing of ERP expertise from outside Zambia. Multiple potential benefits of ERP education on organisations were described and challenges that reduced the impact of ERP education on environmental, project-related, and organisational challenges were explained. The contribution to practice is an ERP education explanatory model that can be used to foster collaboration between industry and academia, to assist universities in appropriately integrating ERP systems into university curricula, and to assist organisations in maximising their benefit from graduates with ERP education. The contribution to theory is a description of the Zambian ERP context and a holistic explanation of how contextual factors impact and are impacted by ERP education. The study underscores the importance of contextual factors when incorporating new information systems' courses into university curricula
Sociodemographic and work-related factors associated with psychological resilience in South African healthcare workers
Get PDFBackground: Psychological resilience facilitates adaptation in stressful environments and is an important personal characteristic that enables healthcare workers to navigate the challenges encountered in their occupation. To date, there is not much information available on factors associated with psychological resilience in South African healthcare workers. Objectives: To determine the prevalence, sociodemographic and work-related factors associated with psychological resilience in a group of South African medical doctors and ambulance personnel. Materials and Methods: This analytical cross-sectional study used secondary data obtained from two cross-sectional studies conducted in healthcare workers. This study investigated the factors associated with resilience as measured by the Connor-Davidson Resilience Scale-10. Inferential analysis was computed to assess the association between independent variables and resilience. Results: A total of 647 healthcare workers were included in the study, consisting of 259 doctors and 388 ambulance personnel. The healthcare workers had low resilience scores (27.6 ± 6.6) overall, with ambulance personnel having a higher average resilience score (28.0 ±6.9) compared to doctors (27.1 ± 6.0) (p = 0.006). Significantly higher resilience scores were observed for doctors: in males (p < 0.001), higher income earners (p = 0.020), current smokers (p = 0.012); for ambulance personnel: previous users of alcohol (p = 0.002). Significantly lower resilience scores were observed in participants with a mental health condition (doctors: p = 0.037; ambulance personnel: p = 0.010), being on treatment for a mental health condition (ambulance personnel: p = 0.029) and feeling the need to drink alcohol to manage work-related stress (doctors: p = 0.034; ambulance personnel: p= 0.048). Multivariable analysis confirmed that current smoker status (β: 3.52, 95%CI: 0.89 – 6.16, p = 0.009) and higher salary in doctors (β: 5.11, 95%CI: 1.46 – 8.177, p = 0.006), and previous alcohol use in ambulance personnel (β: 3.22, 95%CI: 1.10 - 5.34, p = 0.003) were protective against low resilience. Female sex (β: -1.77, 95%CI: -3.39 - -0.15, p = 0.032) and over-time work in doctors (β: -5.11, 95%CI: -9.42 - -0.80, p = 0.006) increased the likelihood of low resilience. Conclusions: Resilience was relatively low in this group of South African healthcare workers. The strong association between low resilience and individual and workplace factors such as female gender, lower income, high over-time worked, mental health status and substance use provide avenues for early intervention and provision of greater support to healthcare workers in low-and middle-income settings
Entrepreneurial Intentions of South African university students: an application of the theory of planned behaviour
Get PDFThis study investigated the Entrepreneurial Intentions (EI) of South African students at three universities in the Western Cape, using the Theory of Planned Behaviour (TPB). The research employed a two-phase design, starting with a less dominant qualitative exploration through nine interviews with students. Subsequently, a more prominent quantitative phase was carried out using an online survey questionnaire. The primary objective was to determine whether the TPB model influences EI over and above situational factors (prior entrepreneurial experience and knowledge of entrepreneurial support) and demographic variables. Contextual measures obtained from the qualitative phase, such as load-shedding and the South African economy, were also incorporated into the questionnaire. Usable responses were received from 523 students (N = 523), allowing for rigorous statistical analyses, including Confirmatory Factor Analysis, Exploratory Factor Analysis, and reliability assessments. Hierarchical Regression Analyses indicated that the TPB explained approximately 48.8% of the variance in EI over and above the situational, demographic and contextual factors. Of all the predictors of EI examined in this study, only race and prior entrepreneurial experience were found to significantly add to the predictive power of TPB in explaining EI. The findings suggest that the TPB influences EI among South African students, over and above situational, demographic and contextual factors
In vitro metabolism studies to inform physiologically-based pharmacokinetic modelling of mefloquine, ritonavir and proguanil
Get PDFClinically observed variability in drug exposure has various negative implications, ranging from an increased possibility of adverse drug reactions to treatment failure. A key contributor to this variability is the contribution of drug metabolism, substantially mediated by the cytochrome P450 (CYP) enzyme superfamily. Thus, a valuable step in assessing the contribution of drug metabolism to variability in drug exposure is the measurement of the kinetics of CYP-mediated metabolism. However, this in vitro data needs to be translated to whole body in vivo clearance, which is also impacted by the physicochemical properties of a drug and how the drug interacts with physiological environments in the body. One method of doing so is through the use of physiologically based pharmacokinetic (PBPK) modelling. By combining in vitro data with available knowledge on the physicochemical properties of a drug PBPK modelling provides a mechanistic understanding of drug exposure. As such, the in vitro metabolic characteristics of 3 commonly used drugs, namely mefloquine, proguanil and ritonavir, were measured. This was done by measuring the microsomal metabolism of these drugs in human liver microsomes, then determining the fraction of the drug metabolized by CYP (fm,CYP) isoforms and confirming this metabolic pattern using recombinant CYP enzymes. In the case of mefloquine, it was found that the drug was metabolized mainly by CYP3A and CYP1A2. While mefloquine metabolism by CYP3A is widely reported, this is the first report of its metabolism by CYP1A2. Proguanil was found to be metabolized by a number of enzymes, namely CYP1A2, CYP2D6, CYP2C19 and CYP3A. This confirms reported data for CYP2C19 and CYP3A, and provides new data for CYP1A2 and CYP2D6. Lastly, ritonavir was found to be metabolized by CYP2D6 and CYP3A. These determined fm,CYPs were then used, along with available data from literature, to develop PBPK models for mefloquine, proguanil and cycloguanil as a metabolite of proguanil using a middle-out approach with the use of Simcyp modelling software. These models were verified by comparing the pharmacokinetic (PK) profiles they simulated to various PK profiles found in literature. The verified models were then applied to various scenarios of interest. In the case of mefloquine, these applications showed that in vitro data does not accurately scale to in vivo clearance which excludes the possibility of doing a bottom-up model for this compound. The verified PBPK model built using this data demonstrates the expected drug- drug interaction between mefloquine and a CYP1A2 inhibitor, fluvoxamine. The model also shows the limited effect of population differences on mefloquine PK, including the reported finding that polymorphisms of CYP3A5 do not affect mefloquine PK. Disease state may therefore have a bigger effect on the variability in mefloquine PK than variability in metabolism does. The model application for proguanil focussed on the potential effects of various CYP genotypes on proguanil metabolism given the number of polymorphic CYPs found to be involved in its metabolism. The effect of CYP2C19 polymorphisms on proguanil and cycloguanil exposure could be clearly demonstrated. Variability in metabolism by other CYPs does not have as big an impact on proguanil exposure, likely because of their lower contributions to the metabolism of the drug. Finally, a previously developed and verified ritonavir model was used, in conjunction with the mefloquine model developed and verified here, to explore the use of ritonavir as an inducer and inhibitor of CYP3A activity. This showed the limited ability of ritonavir to induce mefloquine metabolism, with it being a more capable inhibitor. The ability of ritonavir to induce CYP1A2 activity was also explored using the available model by optimizing its CYP1A2 induction capabilities through parameter optimization. This showed the importance of taking this induction into account when conducting DDI studies between ritonavir and substrates of CYP1A2. Overall, this work addresses gaps in the understanding of the in vitro metabolism of mefloquine, proguanil and ritonavir, and demonstrates how this data can be combined with PBPK modelling to understand and predict PK variability
Difficulties and challenges in implementing screening for lung cancer in high-risk group patients in the respiratory clinic at Groote Schuur Hospital
Get PDFIntroduction: Lung cancer is the leading cause of cancer related deaths in South Africa. The high prevalence of cigarette smoking in our population continues to contribute to the high burden of lung cancer. Screening high risk groups with annual low dose computed tomography (LDCT) has demonstrated the potential benefit of being able to identify individuals with early-stage disease and offer potential curative therapy from this deadly disease. Objective: To determine the barriers and challenges of implementing lung cancer screening in a group of high-risk patients with underling Chronic Obstructive Pulmonary Disease (COPD). Methods: We retrospectively analysed patient records of COPD patients attending the respiratory clinic at Groote Schuur Hospital, Cape Town in the year 2022. Eligibility for lung cancer screening included formal diagnosis of COPD, age 55-74 years, at least 30 pack year history of smoking or stopped smoking within the past 15 years, no history of lung cancer, good general health, fitness for surgery and patients' willingness to undergo further invasive investigations and treatment. Fitness for surgery was objectively determined by a modified Medical Research Council (mMRC) score less than 3 and FEV1 greater than one litre. Results: 116 patients with COPD were screened for eligibility for lung cancer screening. The mean (SD) age was 62.84(10.4) years and 56.1% were male. 44 (37.9%) patients were current smokers, 68 (58.6) were ex-smokers and 4 (3.5%) never smoked. Hypertension (46.6%) was the most common medical comorbidity, followed by previous tuberculosis (19.0%) and diabetes (7.8%). 16 (13.8%) patients were potentially eligible for lung cancer screening. 47 patients had a FEV1 < 1L, 54 participants had a mMRC of 3 and above and 38 patients were excluded because of age. Conclusion: Common clinical factors which made patients ineligible for lung cancer screening in our study are age and poor surgical candidates based on mMRC class and low FEV1. Tertiary service severe/multimorbid COPD clinics provide few patients for lung cancer screening, community-based service may provide a better yield of patients for active lung cancer screening