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An exploration of the (changing) roles, functions and challenges experienced by policewomen in the operational environment of the SAPS: Western Cape Province
Full text linkScholarly interest in gender and policing has grown exponentially over the past two decades. This study is situated within that body of literature and explores the changingrole, functions and challenges experienced by policewomen appointed in the operational policing environment of the South African Police Service (SAPS). The intent is to develop insight into the first-hand experiences and perceptions of operational policewomen and to inform practice initiatives that accommodate the specific needs of policewomen entering the operational sphere of policing in the SAPS. The overall research question in this study is: How has operational policewomen experienced and perceived the challenges and barriers encountered in the execution of their respective policing roles in the masculine domain of operational policing in the SAPS over the last twenty years? The question is explored by focusing on police women in the province of the Western Cape. Exploratory-descriptive research was done by adopting a qualitative research design. A semi structured interview schedule was utilised for one-on-one interviews and one focus group session with a sample of fifteen experienced operational policewomen, with rank levels ranging from Major General to Lieutenant Colonel. The sample size although relatively small can be deemed representative of the whole as the number of commissioned operational policewomen in the Western Cape province is limited. Collected data was analysed by means of thematic analysis and presented as narratives focussing on four major themes. The conclusions drawn from the study indicate that the evolvement and broadened scope of policewomen in operational policing are achieved through personal efforts and determination despite challenges encountered in navigating career paths in policing. Although not well represented in all operational environments in the WC, policewomen are making valuable contributions. Not only do they add critical value in enhancing operational effectiveness but also contribute towards enhancing police legitimacy, regardless of their minority status within the police organisation
The importance of beachgoers as a source of beach litter
No full textThe increasing prevalence of anthropogenic litter on beaches is a significant environmental concern. Various waste materials, including plastics, wood, metal, and paper, often enter coastal environments through direct disposal or indirect pathways such as rivers, storm drains, and beach and ocean users. This pollution poses serious threats to the aesthetic and recreational value of beaches, local economies, and the well-being of beachgoers. Additionally, it has detrimental impacts on terrestrial and marine ecosystems. Reducing litter on beaches requires an understanding of key pollution sources to implement effective mitigation actions and strategies. Beach litter could originate from various sources, including beachgoers. When attributing sources to beach litter, various approaches have been applied but all have shortcomings. This study evaluates the dry and wet sand methodology, which was devised by Barnardo and Ribbink (2020) and Ryan et al. (2020b) and has since been used by Barnardo et al. (2021) and Okuku et al. (2020) to identify beach litter originating from beachgoers, although it has not been validated. I compared litter accumulation at two urban beaches in False Bay, South Africa: Muizenberg, a popular recreational beach, and Sunrise Beach, a nearby, less utilised beach. Data from April 2023, when beaches were open to visitors, were compared to April 2020, when beaches were closed during the COVID-19 pandemic. Findings examined whether the dry sand component reflected differences between years with and without visitors, providing insight into the method's effectiveness. I recorded greater litter loads at Muizenberg than at Sunrise Beach during both sampling years. Between sampling years, more litter was collected during 2020 than 2023 at both beaches. More onshore winds in 2020 likely contributed to litter deposition, while in 2023, when visitors were present, informal beach cleaning would have contributed to the presence of less litter. Litter composition varied by sampling years and beaches. At Muizenberg in 2023, dry sand items were dominated by smoking-related items (mainly cigarette butts) and items made from paper. At Sunrise, single use plastics (such as food and packaging items) dominated in both sampling years. In 2023, dry sand litter accounted for 23% of items and 43% of litter mass at Muizenberg, compared to 6% and 12% at Sunrise, respectively. The amount and composition of the dry sand litter at Muizenberg suggests a correlation with the number of beachgoers the day before, which indicates the potential to use the dry and wet sand method as a proxy for litter generated by beachgoers. I applied the dry and wet sand daily accumulation method to infer the relative contribution of beachgoers to litter loads seasonally at both beaches. The proportion of dry sand litter was higher in summer (when the number of beachgoers was greater) at both beaches compared to other seasons, especially at Muizenberg. Items made from paper and smoking-related items (mainly cigarette butts) dominated by number and mass on the dry sand, especially in summer. On the wet sand, smoking-related items predominated by number and large non-plastic items (such as a car tyre, processed wood, etc.) by mass, mainly in the winter rainy season. These findings suggest that more effective mitigation measures are needed, particularly during summer. These could include increased educational awareness campaigns, the installation of additional waste bins, and increased beach clean-up efforts. I also investigated whether beachgoer litter is a major source of litter in the surf zone. I compared the composition of litter in the surf zone to that on the sandy beach over 50-days in 2022/23, repeating a previous study performed in 2013/14. Daily net tows in the surf zone revealed that litter abundance had decreased since 2013/14. A negative correlation between surf zone litter and the number of beachgoers the previous day suggests that little of the surf zone litter derives directly from beachgoer activity. It is more likely that weather conditions influence both the amount of surf zone litter and beach attendance. Most litter sampled in the surf zone was smaller than that collected on beaches because the 5 mm-mesh net used to sample in the surf zone collected smaller items than items collected by hand on the beach > 10 mm. During offshore winds, small amounts of litter typically found on the dry sand were collected from the surf zone on a few of the sampling days. Findings suggest that only a small fraction of beach litter migrates offshore via the surf zone. In addition, 35% of the litter collected in the surf zone in 2022/23 and 18% in 2013/14 showed signs of weathering, indicating a prolonged time in the sea. In summary, this study validates the use of the dry and wet sand daily accumulation methodology for assessing beach litter contributions from beach users. It also highlights seasonal variations in litter accumulation, particularly on urban beaches. Dry sand litter was most prevalent in summer, linked to an increase in the number of visitors and their tendency to leave waste behind However, there was no strong evidence linking beachgoer litter to the amount in the adjacent surf zone. While findings suggest that only a small proportion of sandy beach litter generated by beachgoers migrates into the nearby sea, interventions to manage beach littering, such as more waste bins, public awareness campaigns, and stricter enforcement policies would be beneficial
Evaluation of forensic DNA profiling success on teeth that have been submerged in the ocean
No full textDeceased humans that are recovered from marine environments contribute to the burden of unidentified bodies, both globally and in South Africa. Compromised conditions of these bodies make identification difficult. In these instances, DNA analysis becomes an invaluable tool for identification. Nonetheless, there is a notable gap in existing literature regarding the use of DNA from teeth for identifying human remains recovered from marine environments. This study therefore aimed to evaluate forensic DNA profiling success on human teeth samples (n = 90) that were submerged in two different marine locations along Cape Town's coastline. Thirty adult volunteers each donated three wisdom teeth, where each tooth per individual was subjected to a different condition for 20 days: one was submerged in False Bay, one was submerged in Table Bay and the remaining tooth was kept as an unsubmerged, matched control in the laboratory. DNA was extracted and quantified using quantitative polymerase chain reaction before undergoing DNA profiling. No significant difference was observed in the likelihood ratio between DNA recovered from samples submerged in Table Bay (median: 1.031 × 1013; range: 4.221 to 5.633 × 1031) compared to False Bay (median: 3.501 × 1015 range: 1.557 × 103 to 2.578 × 1035). As expected, matched control samples yielded significantly higher DNA concentrations than submerged samples and showed significantly higher Likelihood ratios (median: 3.094 × 1028; range: 11.11 to 1.614 × 1033) than submerged samples (p < 0.001). Three DNA profiles from False Bay samples showed no allele detection and therefore were uninformative. Further, allele drop-ins were observed in three DNA profiles from False Bay samples but none in Table Bay samples. These were hypothesised to be due to the presence of marine microbial DNA and could potentially confound DNA interpretations. Overall, the results suggested that the protocol used was suitable for DNA profiling of teeth samples recovered from Table Bay and further research is required to obtain insight into aquatic conditions affecting samples submerged in False Bay
Investigating the role of sestrin 1 and sestrin 2 in preclinical models of tuberculosis disease
Full text linkDespite efforts to eradicate Tuberculosis (TB), Mycobacterium tuberculosis (Mtb), a causative agent for TB, can persist, and the emergence of drug resistance, emphasizes a dire need for new effective treatments and vaccine candidates. Recent understanding of TB immunology has shown hyperinflammatory responses causing damage to lung tissue structure and function, increasing pathology and severity of disease. This has sparked a search for anti-inflammatory modulators for Host Directed Therapies (HDT) to attenuate the effects of prolonged inflammation during chronic TB and persist after the completion of the therapy. Using Cap Analysis of Gene Expression (CAGE) transcriptomics, we identified a family of genes, Sestrins (Sesn 1 and Sesn 2), which showed differential expression after Mtb infection, particularly in Sesn1 where expression was significantly reduced, alluding to a possible role of Sestrins during TB disease. Sestrins are a family of antioxidant genes that have shown anti-inflammatory and metabolic modulatory roles in various disease models including cardiomyopathy, mitochondrial dysfunction, insulin resistance, and neurodegenerative diseases. However, the potential role of these genes remains unknown in TB, and conducting infection studies would contribute novel information to the TB field. By generating Sesn2 and macrophage-specific Sesn1 knockout mouse models, we uncovered the role of these genes for the first time in inflammation and TB disease. Here, we have shown that the deletion of Sesn1 (macrophage-specific) and Sesn2 (null) mice were undistinguishable from control animals at a naïve state. During TB disease, we demonstrate that global ablation of Sesn2 results in a significant increase in inflammation at later stage of Mtb infection and increased mortality. The increased inflammation was associated with enhanced total lung and lymph node cells, immune cell recruitment and lung tissue pathology. In contrast, macrophage-specific deletion of Sesn1 had no effect on the outcome of Mtb infection. To understand the mechanism, we found Sesn1- and Sesn2- deficient macrophages showed increased bacterial growth, pro-inflammatory response, and higher levels of cell death. We found reactive oxygen species, known to potentiate tissue damage, are associated with Sestrin ablation. Moreover, Sestrins are closely linked to metabolic regulation, Seahorse analysis showed that the absence of Sesn1 or Sesn2 hinders the ability of macrophages to regulate energy metabolism in the presence of stress, with higher ATP production rate and consistent energetic state, may result in elevated ROS levels. While our findings do not directly establish ROS as the primary driver of pathology in Sesn2 knockout mice, they suggest modulating inflammatory responses during TB disease
A climate change vulnerability assessment of 58 Richtersveld plant species
No full textThe Richtersveld is the northernmost region of the Succulent Karoo and is located in the north-western region of South Africa's Northern Cape Province. This region has an incredible arid plant diversity, with both the highest succulent plant diversity and highest rate of endemism in an arid area, globally. It forms part of both a global biodiversity hotspot and a UNESCO world heritage site. However, it is already experiencing significant climate change exposure which is predicted to worsen. Changes in the area's climate are also interacting synergistically with other anthropogenic pressures including mining, poaching and agriculture. The threats to this area, including climate change, are documented but knowledge gaps still remain – especially with regards to plants and climate change vulnerability. In this study I aimed to find which Richtersveld species are the most vulnerable to climate change while trialling a relatively novel approach in this context. I used a trait-based assessment with correlative species distribution model outputs to assess the sensitivity, adaptive capacity and exposure of 58 plant species occurring within the Richtersveld National Park. This included assessing biological, ecological, environmental and spatial traits of species that contribute to climate change vulnerability. Traits were scored based on literature, expert opinion and correlative modelling outputs. Trait scores were then combined using both additive and ordinal methods, creating a best-case scenario where unknowns were assumed to have ‘low' scores, and a worst-case scenario when these were assumed to be ‘high'. These scenarios were applied to both the ordinal and additive scoring methods. For the additive scoring method, there was an additional consideration – trait weighting. It would be inaccurate to assume all traits hold the same importance in determining a species' vulnerability to climate change. Each trait was assigned a weighting based on literature and expert opinion and applied in an additional weighted scoring approach. Therefore, each species had a total of six climate change vulnerability scores: a best-case ordinal, a worst-case ordinal, a best-case unweighted additive, a worst-case unweighted additive, a best-case weighted additive and a worst-case weighted additive score. Under the worst-case ordinal scoring method, 34 species (59 %), were scored as highly vulnerable to climate change. The most vulnerable species were those that consistently scored high vulnerability scores, across all six scoring methods. This included Cheilanthes namaquensis (Not endemic to the region nor the park and Least Concern), Trachyandra ardimontana (almost endemic to park and Endangered), Albuca etesiogaripensis (almost endemic to park and Data Deficient), Ruschia glauca (almost endemic to park and Endangered) and Schwantesia herrei (Richtersveld endemic and Least Concern). I also found a mismatch between species' Red List status and their scores in my climate change vulnerability assessment. This suggests that highly climate change vulnerable species identified in this study currently have a low Red List threat status assigned to them by the responsible conservation organisation. This finding could mean that their status does not accurately reflect their level of conservation risk – especially if climate change is not accounted for. This can cause them to be overlooked in terms of conservation resource provision and decision- making. The IUCN Red List Version 16 Section 12 provides guidelines for assessing climate change vulnerability and its application in determining a species' threat status to climate change. However, its development is relatively recent, and its use is limited, possibly due to the data and technical expertise required. My study provides a possible example of how, even in highly biodiverse region with low data availability, climate change vulnerability assessments may be carried out, and of the value for preventing extinctions. The highest concentration of climate change vulnerable species were found to be in the central western and northern areas of Richtersveld National Park. The spatial representation of these data may aid where within the Park conservation and management can be prioritized. In conclusion, I trialled an approach that has not previously been applied for Richtersveld plants. The approach produced predictions of climate change vulnerability that could be used for conservation. The approach used in this study helped identify species and areas to which climate change conservation measures could be applied. This approach can be applied to other arid areas and aid in climate- related conservation, including in section 12 of the Red Listing Guidelines (Version 16)
Constructing a family tree in an online space as an act of digital curation: an auto-hermeneutics study
Full text linkDigital curation requires taking appropriate actions throughout the lifecycle of digital data. Digital curation of research data in a lifecycle is referred to as the custodial approach, while the pragmatic approach is the curation of digital content in everyday life, such as on websites or social media platforms (Dallas, 2016). Online genealogy, in which a genealogist is using a digital platform to construct a family tree and search for source documents, is an example of the pragmatic approach to digital curation. In this study I investigate genealogy through the lens of digital curation to discover how users curate their genealogical information on a major genealogy website, Ancestry.com. In this way, I consider how online genealogy can be studied as an example of the pragmatic approach to digital curation. This is a qualitative study making use of auto-hermeneutics – I collected data by systematic self-observation (SSO) and analysed it by interpretative phenomenological analysis (IPA). I reconstructed my own family tree in Ancestry.com, evaluating the research hints offered to me by the website algorithm and the member-constructed family trees which contained my ancestors. I found, among other things, that Ancestry.com makes the tree construction process easy and the research hints provided by the website can be verified if caution is exercised, but the same cannot be said for the family trees constructed by Ancestry.com members, many of whom do not practise caution in this endeavour. Study recommendations include a change in the data fields Ancestry.com uses for data capture from members or a change in which it processes and displays that data to ensure that omission of data does not cause incongruous errors to be displayed; and better visibility of the website's guidance on good research techniques to avoid the perpetuation of research errors. Ancestry.com already has verification functionalities which, if applied more widely, have the potential to improve the curation of member-constructed trees
Anti-cancer effects of aqueous extracts of Dodonaea Viscosa on Burkitt lymphoma
Full text linkAnti-cancer effects of aqueous extracts of Dodonaea Viscosa on Burkitt lymphoma Cancer is a leading public health problem worldwide, and although modern treatments have undeniably improved patient outcomes, many cancers remain refractory or untreatable. New and more effective treatments are needed, and natural phytochemical compounds are a valuable source for the development of such treatments. In South Africa, the high HIV prevalence is a compounding factor in cancer incidence, with some cancers being disproportionately high among HIV-positive individuals. One such cancer is Burkitt lymphoma (BL), a highly aggressive B-cell-derived malignancy, which develops predominantly in HIV-infected individuals. Many cancer patients, especially those from rural communities, use traditional medicine (TM) as an alternative to chemotherapy. While conventional treatments have been thoroughly researched and tested before clinical approval, alternative treatments have not. Therefore, TM may not necessarily be beneficial to patients, could interfere with conventional treatment if used concurrently, and in some instances, be harmful to users. One TM commonly used by communities in the Western Cape regions of South Africa is derived from the plant Dodonaea viscosa. Extracts from this plant have not been widely investigated scientifically, however, preliminary work indicates that it holds potential anti-cancer properties. In the current research, the inhibitory potential of D. viscosa extracts (DVE) on BL was comprehensively assessed, using in vitro assays, as well as using an in vivo mouse model. Using cell viability assays, the IC50 of DVE on two BL cell lines, namely Ramos and BL41, was determined. The Ramos IC50 was 0.06 mg/ml while that of BL41 was 0.18 mg/ml. Notably, the noncancerous lymphoblastoid control cell line (LCL) was significantly less sensitive to DVE compared to both BL cell lines with selectivity indices of 2.8 (using IC50) and 1.7 (using IC30) for Ramos and BL41 respectively. Cell Trace proliferation and colony formation assays showed retardation in the proliferation of extract-treated BL cells (3.2-fold and 10.9-fold reduction in progress to daughter cell generation relative to untreated for Ramos and BL41 respectively). Additionally, DVE induced significant apoptosis, as shown by cellular morphological analyses, Annexin V and caspase 3/7 activity assays, cell cycle profiling and western blotting, showing enhanced expression of effector apoptotic markers (cleaved caspase 3 and cleaved PARP). The PI3K/Akt pathway, which is often altered in BL and known to drive lymphomagenesis, was found to mediate, at least partially, the cytotoxicity of DVE - the PI3K inhibitor p-PTEN was upregulated, leading to upregulation of its target p-PDK1. Additionally, the effector molecule p-AKT (ser 473) and p-GSK3 were altered. Lastly, using a BL xenograft mouse model, DVE was found to be significantly less toxic than the approved drug Doxorubicin, and to slow down tumour growth over time. This study revealed that aqueous extracts from the Dodonaea viscosa plant, used by traditional healers, is a valuable source of lead compounds for the development of novel therapeutics in the treatment of Burkitt lymphom
The Application of Taguchi Experiments in Developing Gecko-Inspired Dry Adhesive for Macro-Handling Applications
Full text linkSynthetic dry adhesives have been developed to mimic the gecko’s adhesion using lithography and micro-machining of a mould to cast a suitable elastomer. Previous international studies used nano-manufacturing processes, which are expensive and are not readily available in South Africa. In this study, a simple micro-machining method was used using a three-axis milling machine and Vytaflex 30 to develop an adhesive pad. The Taguchi method to design experiments was used to determine the optimum machining conditions to create micro-wedges. The results show that, although a maximum adhesion pressure of 1,924 Pa was obtained with a preload pressure of 1,323 Pa, the adhesion force produced might not be suitable for macro-handling applications
The neo-Roman conception of freedom in developmentalism: A historical perspective
Full text linkDoes the statism of developmentalism have no regard for freedom? This paper re-examines political and theoretical premises of the developmentalist tradition in economics and argues that it embeds a conception of freedom known as neo-Roman freedom, distinct from that of the liberal tradition and more recently, the capability approach. To this end, the writings of four key periods/schools in the developmentalist tradition, that form the case studies of this paper, are reviewed. These are: Early Modern Europe, the American School, Meiji Japan and the Latin American School. While both the liberal tradition and capability approach focus on the individual as the primary unit of analysis, the neo-Roman conception views the freedom of the individual as derivative of the freedom of the collective, embodied by the state. Thus, this analysis – the legacy of the Roman Republic and the concept of the free state as formulated by Niccolò Machiavelli – sees in national sovereignty the path to securing individual freedoms. Also discussed is why developmentalism, through history, has aimed at industrialisation of countries in the periphery. This paper suggests that the answer is more political than economic, that is, industrialisation provides the material basis for national autonomy through the development of autonomous productive capabilities
Determinants of functional capacity and work ability post SARS-COV-2 infection in miners
Full text linkBackground: Insufficient data exists on the sequelae of COVID-19 and its impact on function and work ability among workers. The aim of this study was to investigate the determinants of functional capacity and work ability in miners following COVID-19 disease. Methods: This cross-sectional study recruited 204 mine workers employed at a ferromanganese mine in the Northern Cape province of South Africa with a confirmed laboratory diagnosis of COVID-19 within the past 12 months. Study instruments included a socio-demographic questionnaire, Post COVID-19 Functional Scale (PCFS), Work Ability Index (WAI), chest radiograph and the Two-minute Walk Test (TMWT). Data analysis was done using STATA version 16 to generate univariate and multivariate quantile regression models. Results: The majority (74%) of the participants were males with a mean age of 38.8 years and employed in the mining department (46%) as operators. A third were current smokers (35%), and obese (36%). The most commonly reported acute COVID-19 symptoms were sore throat (56%), cough (43%), and anosmia (34%). Almost all the participants had reported having two or more episodes of COVID-19 which was of a mild form (64%). Most (86%) returned to work within 14 days of diagnosis. None of the miners had an abnormal PCFS score, nor did they have poor WAI scores. Aside from living arrangements (living with a spouse), none of the socio-demographic or occupational factors were associated with COVID-19 disease severity. Unlike for COVID-19 disease, female sex was significantly associated (p<0.001) with poor performance on the TMWT in the simple regression models. After adjusting for disease severity and sex in the multivariate models, no significant association was observed between COVID-19 disease and the TMWT distance. Conclusion: This study found limited evidence of impaired functional capacity and work ability in miners following COVID-19 disease within one year of SARS-CoV-2 infection. Furthermore, only female sex, but not COVID-19 was associated with impaired functional ability