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Carbon quantum dots as a co-reactant to Ru(bpy)32+ for electrochemiluminescence biosensing of cardiac troponin I
No full textCarbon quantum dots are interesting materials for electrochemiluminescence as they can be used as luminophores and co-reactants. This research paper focuses on the use of carbon quantum dots as the co-reactant to Ru(bpy)32+ in an electrochemiluminescence system. Most of the work reported in literature applied the Ru(bpy)32+ /CQD ECL system for chemical sensors. In this work, we apply it to a biosensor for the detection of cardiac troponin I. The Carbon quantum dots were synthesized using a bottom-up method and were used to modify the surface of screen-printed electrodes for immobilization of the biomolecules. They were characterized by photoluminescence, ultraviolet-visible, Fourier transmission infrared spectroscopy and square wave voltammetry. When the carbon quantum dots were introduced to the system, an enhancement in the electrochemiluminescence intensity of Ru(bpy)32+ was observed. An electrochemiluminescence immunosensor was developed for the detection of cardiac troponin I. Electrochemiluminescence immunosensor achieved a low limit of detection of 0.02 ng/mL. The sensor also had a detection time of 15 min, allowing for rapid detections
Experiences of simulated patients in clinical skills laboratory: a qualitative study
No full textBackground: Nursing simulations with simulated patients (SPs) have proven effective in creating realistic opportunities to enhance the students’ clinical competence within a safe learning environment. This setting helps to reduce anxiety and increases self-confidence among health sciences students. This study aimed to explore experiences of SPs in clinical skills laboratory of a Department of Nursing at a university in Western Cape. Objectives: Objectives were set to explore the contextual elements of SPs’ experiences during clinical skills sessions, identify educational design aspects from those experiences and assess their views on student outcomes. Method: A qualitative descriptive, exploratory and contextual design was used. Data were collected through semi-structured interviews with eight SPs. The data were coded to develop emerging themes and sub-themes, following Braun and Clark’s systematic analysis process. An independent coder reviewed findings, and themes were confirmed during a consensus meeting. Results: This study found that SPs engaged in multiple role-play consultations, improving their understanding of healthcare consultation structures and rules. They recognised their roles in achieving the outcomes needed for students. Conclusion: This study confirmed existing literature on SPs in a clinical skills laboratory within a Department of Nursing. Participant interviews provided verbatim quotations that enriched findings. Contribution: The study aimed to recommend ways for a Department of Nursing to support SPs in improving their laboratory skills and enhancing student learning
HF-Induced Modulation and Electron Temperature Effects in PMSE: VHF Spectral Diagnostics and Dusty Plasma Interpretation
No full textThis study presents the first experimental investigation of Polar Mesospheric Summer Echoes (PMSE) response to high-frequency (HF) pump power modulation using the EISCAT VHF radar system. Two modulation schemes were employed during a recent campaign: stepped-power modulation (24 July 2019) and quasi-continuous power sweeping (26 July 2019). Coherent VHF radar spectra were analyzed to evaluate the impact of HF heating on PMSE characteristics. Results consistently show a contraction in the VHF spectral area with increasing HF pump power (40–80 kW), indicating suppression of small-scale electron density irregularities. This spectral narrowing is attributed to enhanced diffusion and dust charging processes driven by elevated electron temperatures. The ratio of diffusion to charging timescales (Formula presented.) is used as a key diagnostic to interpret these changes. Numerical simulations incorporating realistic dust cloud parameters reproduce the observed trends and reveal layer-specific responses, with lower PMSE layers exhibiting stronger overshoots and higher dust densities. These findings demonstrate that the spectral area under the VHF echo serves as a sensitive proxy for electron temperature enhancements during HF heating, offering a valuable diagnostic tool for studying mesospheric turbulence and dusty plasma dynamics
Promoting first people tourism in the Western Cape: A comparative study of Ratelgat Farm and !Khwa ttu San Cultural Education Centre
No full textThe importance of the appreciation of the history and heritage of First People globally cannot be underestimated, and inclusive, integrated tourism can support the recognition thereof. First People are often referred to as indigenous and the first ethnic-cultural groups who are the earliest known inhabitants of an area. First People tourism refers to tourism initiatives that are owned by the majority and managed and operated by First People and their associates who, in turn, have connections and responsibilities towards local indigenous people and the cultural and biophysical spaces in which such operations are located. A wealth of literature supports and critiques the sustainability of cultural villages as tourist facilities. The purpose of this study was to revisit the role played by two tourist facilities in the Western Cape in the sustainable development of First People tourism as well as the fostering of an appreciation of their history and heritage. These facilities are Ratelgat Farm and !Khwa ttu San Cultural Education Centre. Ratelgat Farm was managed by the Griqua Development Trust and supported by the Government of South Africa and CapeNature, the latter being the conservation authority in the Western Cape. It is located on Route N7 close to the town of Van Rhynsdorp and offered traditional Griqua cultural experiences to visitors. During the research, it was discovered that Ratelgat Farm was no longer operational; therefore, other cultural sites were considered for comparison. The !Khwa ttu San Cultural Education Centre is located on Route R27 on the West Coast near the town of Yzerfontein and, among others, offers the following related to San Peoples: San guided nature experience, discovering the value of fynbos, visiting a replica of a traditional San village, storytelling and survival skill experiences. Access and benefit sharing (ABS) was used as the theoretical framework to assesses the contributions of the sites critically. The qualitative survey methodology underpinned the study, which largely drew on observation of participants analysing visitors’ books, and interviews with tourists and the management of the facilities, as data-gathering tools. The purpose of the study was to analyse the economic, cultural, ecological and managerial factors that might, or indeed were affecting the sustainability of San and Griqua tourism in the Western Cape as a largely western-oriented tourism destination
Antioxidant and antimicrobial activities of green-synthesized silver nanoparticles using a cocktaila aqueous extract of capparis sepiaria root and tabernaemontana elegans bark
No full textThe increasing incidence of antimicrobial resistance (AMR) poses a serious threat to public health, which necessitates the development of alternative countermeasures to combat it. Green nanotechnology, in particular the use of silver nanoparticles (AgNPs), shows promise in combating AMR. Although the synthesis of AgNPs using medicinal plant extracts has been explored, combining extracts from two medicinal plants to synthesize AgNPs with enhanced properties has received less attention. Therefore, this study addresses this gap by presenting the green synthesis of AgNPs using a cocktail of Capparis sepiaria–Tabernaemontana elegans (CsTe) aqueous extract as reducing, stabilizing, and capping agents. The focus is on assessing the antioxidant and antimicrobial activities of the synthesized CsTe-AgNPs. Various parameters, such as pH, temperature, extract and silver concentrations,
reaction ratio, and synthesis time, were optimized to enhance the efficiency of CsTe-AgNPs synthesis. The CsTe- AgNPs were monodispersed and spherical, with an average core
size of 14 ± 2.953 and 7 ± 3.849 nm, and hydrodynamic size of 23 ± 12.260 and 138 ± 2.086 nm for pH = 6 and pH = 11, respectively. The FTIR analysis revealed a shift in peaks of
biomolecules present in the CsTe extracts that could be responsible for the reduction of Ag salt to form CsTe-AgNPs. Notably, CsTe-AgNPs_pH11 had potent antimicrobial activity, with a minimum inhibitory concentration (MIC) of 12.5 ± 0 μg/mL against K. pneumoniae and P. aeruginosa, and a slightly higher MIC for C. albicans of 25 ± 5.449 μg/mL. This study demonstrated the effectiveness of using a mixture of two extracts to synthesize AgNPs with enhanced antioxidant and antimicrobial activities, and therefore, could serve as a promising reagent to combat AMR
Human resource management in a district health system in the public health sector
No full textOrientation: There is a misalignment between the strategic goals of the public health sector, which include strengthening health systems to produce desired health outcomes, and the human resource management of the human resources for health. Research purpose: This study aimed to describe the extent and identify the factors influencing the human resource management in achieving the strategic objectives of the public health sector. Motivation for the study: Managers in the public health sector can develop interventions and effective procedures to improve alignment in the human resource management of the human resources for health to improve health outcomes. Research approach/design and method: A qualitative descriptive study design with an interpretivist approach was utlised to conduct the study. A document review and sixteen face-to-face interviews were conducted, eight human resource (HR) practitioners and eight line managers purposively selected from an urban and rural district. Main findings: The public health sector provides a unique context that requires different considerations for human resource management. Human resource managers and line managers do not only have different backgrounds and orientations but they also function in different contexts (administrative vs. clinical) in the public health sector. The factors influencing effective human resource management are as follows: the lack of capacity to implement key HR strategies in the public health sector, competing priorities and the absence of clear roles in performing human resource practices. Practical/managerial implications: There is a need to foster a partnership approach between the HR manager and line manager to provide effective human resources management as it is complex and fractured, particularly during change and decentralisation. Contribution/value-add: This article addresses the research gap on human resource management in the public health sector shifting focus from individual practices to a systems thinking approach in strengthening human resource management. It also makes a theoretical contribution by adding context to human resource management as a key requirement for implementation decision making
Cytotoxicity of methamphetamine exposure on sertoli cells: a pilot study with implications for male infertility
No full textMethamphetamine (Meth), a psychoactive drug, has been shown to reduce testicular weight and decrease sperm count, indicating its potential role in contributing to male infertility. We therefore assessed Meth’s effects (0.1–100 μM) on TM4 Sertoli cell viability, toxicity, and proliferation (trypan blue exclusion assay), mitochondrial activity (MA) (XTT assay), while transepithelial electrical resistance (TEER) was used to examine monolayer permeability. The acute study (only 24-hour Meth exposure) mimics recreational users and the chronic study, the Meth addicts who require daily doses (24–96 hours). Acute Meth treatment had minimal impact on TM4 Sertoli cell viability and toxicity, while chronic exposure resulted in reduced cell viability and increased toxicity in a dose-related manner. Acute exposure suppressed cell division at 72 hours, while chronic exposure suppressed cell division at both 72 and 96 hours. Long-term suppression of MA was observed for both acute and chronic Meth exposure (20 µM and 100 µM). Both acute and chronic Meth exposure affected permeability across the blood–testis barrier (BTB), which persisted for up to 96 hours. Given the pivotal role of Sertoli cells in spermatogenesis, our findings provide a two-pronged mechanism for Meth-induced male infertility and indicate that short-term exposure may have long-term effects on the germinal epithelium. © 2025 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group
Factors shaping Covid-19 vaccine acceptability among young people in South Africa and Nigeria: an exploratory qualitative study
No full textCovid-19 vaccine hesitancy among young people can be seen as an acute – but not isolated – phenomenon within an alarming longer-term trend of broader vaccine distrust in Africa. Yet there are still considerable knowledge gaps in relation to the scope and drivers of low vaccine acceptability among young people. Moreover, better frameworks and tools are needed to conceptualise and better understand acceptability in this population group. We applied the recently published Accelerate Framework for Young People’s Acceptability to guide qualitative research with young people living in South Africa and Nigeria. We aimed to investigate their overall acceptability of the Covid-19 vaccine, and explore factors shaping this acceptability and willingness to be vaccinated. In collaboration with seven community-based organisation partners, we conducted 12 in-person focus groups and 36 remote interviews with 163 individuals aged 15-24. Through a collaborative, iterative process we conducted thematic analysis, incorporating aspects of both deductive and inductive approaches. Our findings show how vaccine acceptability is shaped by a multiplicity of inter-related factors. They also provide a more in-depth perspective of some of these phenomena, their relative importance and their connections in this group of young people. Limited vaccine understanding, conflicting information and distrust, the influence of others, and fear of side effects were key inter-related drivers of low vaccine acceptability. Factors promoting Covid-19 vaccine acceptability were instead: positive perceptions of vaccine safety and efficacy, protection from disease, protection of others, and a desire to return to normal activity. We discuss implications of these findings for policy and practice, both to increase acceptability of Covid-19 vaccination among young people, and more broadly promote vaccination as a critical component of public health programs. Lastly, we reflect on this first application of theAccelerate Framework, and implications for its use in future studies
Understanding dominant hydrological processes and mechanisms of water flow in a semi-arid mountainous catchment of the Cape Fold Belt
No full textImproving our understanding of streamflow characteristics, water storage, and dominant flowpaths in mountainous regions is important as mountains play a vital role in delivering water to lowlands, particularly in semi-arid areas. This work characterized water sources, flowpaths, and streamflow characteristics in the semi-arid, mountainous Kromme catchment in Eastern Cape Province of South Africa. Precipitation, shallow and deep groundwater levels, and streamflow data were analysed to identify patterns that indicate the occurrence and/or dominance of certain processes, responses, and flowpaths. Results of the study demonstrated how the catchment responds to rainfall events across seasons and rainfall intensities. Steep and rocky areas that make up much of the catchment contributed to significant flood peaks after high-intensity storms. Quick and slow responses in flow after rainfall events indicated the dominance of both surface and subsurface flowpaths respectively. Furthermore, surface and subsurface flows were significant in recharging the floodplain alluvial aquifer as well as maintaining streamflow during dry periods. Average annual runoff coefficients were low (0.09), which implied large evapotranspiration (ET) withdrawals from dominant flowpaths and/or storage in inactive groundwater. The Kromme catchment has a sizeable floodplain with large alluvial aquifers, which make significant contributions to catchment storage and outflows. Overall, the catchment streamflow was sustained by baseflow (for ∼50% of the time)
Dimensionality in confirmatory factor analysis is not in the eye of the beholder: ancillary bifactor statistical indices illuminate dimensionality and reliability
No full textThis tutorial delves into dimensionality assessment within the context of psychological measurement instruments, particularly focusing on bifactor models. It underscores the imperative to move beyond traditional fit indices when evaluating factor structures while highlighting the significance of ancillary bifactor indices such as explained common variance, OmegaH and percentage of uncontaminated correlations in gaining a more comprehensive understanding of the interplay between general and specific group factors. The tutorial offers a step-by-step guide to leveraging the power of R software for confirmatory factor analysis and the acquisition of ancillary bifactor indices. Through practical case studies, it elucidates the potential pitfalls of exclusively relying on fit indices and advocates for a balanced, multifaceted approach to dimensionality assessment. By integrating fit measures and ancillary indices, researchers can draw more informed and nuanced conclusions about measurement instrument dimensionality, ultimately enhancing the precision of psychological assessment