16918 research outputs found
Sort by
The influence of South Africa’s model of devolution in Kenya, Zimbabwe and Zambia: why and how did the model, concepts and texts migrate?
No full textThe constitutional migration of models, concepts and texts is an old phenomenon. In Africa, developing countries are encouraged to learn from each other, especially since most African countries are in transitional stages of development. That is in line with the project of the African Renaissance, which advocates that Africans themselves seek solutions to African challenges and that any assistance from the outside should be tailored to uphold African ownership. The South African Constitution is revered in Africa and beyond as modern and progressive. It is thus not surprising that a number of its constitutional provisions, for example the Bill of Rights or the devolution model, migrated to other African countries. The South African devolution model conspicuously migrated to Kenya, Zimbabwe and Zambia, as evidenced by the resemblances in devolution concepts and texts. However, there is little understanding of how such migration took place. Furthermore, the phenomenon of exporting and importing similar devolution models, concepts and texts has not been the subject of extensive research. Comparative federalism traditionally focuses on the analysis of written constitutions (mostly Western) and their similarities and differences, yet pays only limited attention to constitutional migration, transformation processes, and the import and export dynamics of constitutional migration in the African context. This is the void that this study seeks to fill. The research question in this study examines the influence of South Africa’s devolution model in Kenya, Zimbabwe and Zambia, considering why and how the model, concepts and texts migrated. The research consists of a desktop study of both primary and secondary sources, including systematic, qualitative and in-depth interviews with key actors who were involved in the constitution-making processes of South Africa, Kenya, Zimbabwe and Zambia
Teaching identification as a protective and risk factor for teacher burnout in the context of role stress
No full textBackground: Work-related stress has been linked to severe negative mental health outcomes. In the context of the COVID-19 pandemic, this stress has been exacerbated, with particularly adverse consequences for schoolteachers, who are often referred to as the forgotten frontline workers due to their critical yet overlooked role in sustaining education during crises. The current study was framed within the Job Demands-Resources model and explored the relationship between role stress, as operationalized by role conflict and role ambiguity, and components of burnout. Method: Participants were schoolteachers (n = 355) in South Africa who completed the Role Conflict and Ambiguity Scale, the Professional Identification Scale, and the Emotional Exhaustion and Depersonalization subscales of the Maslach Burnout Inventory. Results: Mediation and moderation analyses revealed that teaching identification had a significant negative association with role conflict (r = − 0.19, p < 0.001), role ambiguity (r = − 0.40, p < 0.001), emotional exhaustion (r = − 0.42, p < 0.001), and depersonalization (r = − 0.38, p < 0.001). Teaching identification significantly predicted lower emotional exhaustion (β = −0.29, p < 0.001) and depersonalization (β = −0.27, p < 0.001). However, in the case of role ambiguity, teacher identification played an aggravating rather than a moderating role as the relationship between role ambiguity and burnout was stronger at high levels of teacher identification. Conclusion: These findings highlight the paradoxical nature of professional identification in shaping teachers’ well-being. The study underscores the organizational need to minimize role stress by providing clear job expectations and structured support systems. It reinforces the importance of implementing measures to enhance teachers’ professional pride while ensuring that their commitment does not lead to burnout
Estimation of hydrogeological spring catchment area: case of Jinci spring in North China
No full textHydrogeological spring catchment area of Jinci spring is the starting point for all hydrogeological analyses and one of the fundamental datasets for karst groundwater modeling. Unfortunately, there is a lack of detailed research on the hydrogeological spring catchment area. To sustainably utilize and protect the karst groundwater resources of Jinci spring, this paper investigates the variation pattern of the spring flow decrease coefficient from 1956 to 1994, estimates the hydrogeological spring catchment area by using the linear regression method and the Turc method. The results show that: (1) The spring flow decrease coefficient generally shows an increasing trend over time, and its variation indicates the time-varying characteristics of the hydrogeological spring catchment area. (2) The hydrogeological spring catchment areas estimated by the linear regression method are 2143, 2084 and 2037 km2, with an average of 2088 km2. (3) The hydrogeological spring catchment area estimated by the Turc method exhibits a series of values, and its time-varying characteristics is the dynamic change with time, resulting from the joint effects of natural and anthropogenic factors. This study provides a theoretical foundation for the protection and management of karst groundwater in the semi-arid region of northern China
Euclid preparation: LXXII. three-dimensional galaxy clustering in configuration space: two-point correlation function estimation
No full textThe two-point correlation function of the galaxy spatial distribution is a major cosmological observable that enables constraints on the dynamics and geometry of the Universe. The Euclid mission is aimed at performing an extensive spectroscopic survey of approximately 20 30 million Hα-emitting galaxies up to a redshift of about 2. This ambitious project seeks to elucidate the nature of dark energy by mapping the three-dimensional clustering of galaxies over a significant portion of the sky. This paper presents the methodology and software developed for estimating the three-dimensional two-point correlation function within the Euclid Science Ground Segment. The software is designed to overcome the significant challenges posed by the large and complex Euclid dataset, which involves millions of galaxies. The key challenges include efficient pair counting, managing computational resources, and ensuring the accuracy of the correlation function estimation. The software leverages advanced algorithms, including k-d tree, octree, and linked-list data partitioning strategies, to optimise the pair-counting process. These methods are crucial for handling the massive volume of data efficiently. The implementation also includes parallel processing capabilities using shared-memory open multi-processing to further enhance performance and reduce computation times. Extensive validation and performance testing of the software are presented. Those have been performed by using various mock galaxy catalogues to ensure that it meets the stringent accuracy requirement of the Euclid mission. The results indicate that the software is robust and can reliably estimate the two-point correlation function, which is essential for deriving cosmological parameters with high precision. Furthermore, the paper discusses the expected performance of the software during different stages of Euclid Wide Survey observations and forecasts how the precision of the correlation function measurements will improve over the mission's timeline, highlighting the software's capability to handle large datasets efficiently
Community literacy club and family language policymaking initiatives for biliteracy development
No full textBackground: Our article analyses two case studies that show an urban South African family and members of a community literacy club engaging in grassroots initiatives as family and community language policymakers and planners for bilingual and biliteracy development. Objectives: The main aim is to describe and analyse the initiatives taken by both community members of the literacy club and family members in challenging separate bilingualism, monoglossic, and anglonormative ideologies. Method: The researchers used linguistic ethnographic methods to collect data and primarily draw on image data, a written text at the literacy club, as well as transcribed data from observational data. Results: The research findings point to the critical role that communities and families play in developing and maintaining children’s home language, as well as desire and uses of more than one language to develop children’s biliteracy. Conclusion: We view children’s biliteracy development in the community and the family as rooted in the sociocultural through a process of drawing from a rich linguistic knowledge and vocabulary that is learned in context. Contribution: Our contribution to the field is in highlighting policymaking from below and how policymaking from above needs to meet language policymaking and planning from below. We also contribute to understandings of simultaneous biliteracy as opposed to separate and sequential biliteracy
VVV-WIT-13: An eruptive young star with cool molecular features
No full textContext. Outburst phenomena are observed at different stages of stellar evolution, due to the enhancement of the mass accretion rate on protostars or even stellar merger events. In the case of a young stellar object (YSO), the episodic mass accretion event plays an important role in the pre-main-sequence stellar mass assembly. Here we investigate an infrared eruptive source (RA = 16:53:44.38; Dec = − 43:28:19.47), identified from the decade-long VISTA Variables in the Vía Láctea survey (VVV). We named this target after a group of variable sources discovered by VVV, as VVV-WIT-13, where WIT stands for ‘What is this?’, due to its unique photometric variation behaviour and the mysterious origin of the outburst. This target exhibited an outburst with a 5.7 mag amplitude in the K s -band, remained on its brightness plateau for 3.5 years, and then rapidly faded to its pre-eruptive brightness afterwards. Aims. Our aim is to reveal the variable nature and outburst origin of VVV-WIT-13 by presenting our follow-up photometric and spectroscopic observations along with theoretical models. Methods. We gathered photometric time series in both near- and mid-infrared wavelengths. We obtained near-infrared spectra during the outburst and decaying stages on XSHOOTER/VLT and FIRE/Magellan, and then fitted the detected molecular absorption features using models from ExoMol. We applied 2D numerical simulations to re-create the observables of the eruptive phenomenon. Results. We observe deep AlO absorption bands in the infrared spectra of VVV-WIT-13, during the outburst stage, along with other more common absorption bands (e.g. CO). Our best-fit model suggests a 600 K temperature of the AlO absorption band. In the decaying stage, the AlO bands disappeared, whilst broad blue-shifted H2 lines arose, a common indicator of stellar wind and outflow. The observational evidence suggests that the CO and TiO features originate from an outflow or a wind environment. Conclusions. We find that VVV-WIT-13 is an eruptive young star with instability occurring in the accretion disk. One favoured theoretical explanation of this event is a disrupted gas clump at a distance of 3 au from the source. If confirmed, this would be the first such event observed in real time
Advancing a circular bioeconomy: unlocking the potential of banana pseudostem for microbially-derived value-added products
No full textBananas have been touted as a vital food crop, that is typically cultivated under tropical climates and generates high volumes of wastes. Of particular interest, banana pseudostem (BP) is a lignocellulosic waste that is renewable, abundant and may serve as a low-cost carbon source for generating a spectrum of high-value bio-based products. However, high production costs have restricted its mainstream adoption. This review explores the suitability of BP as a bioprocessing substrate, assessing advances in pretreatment strategies for enhanced sugar recovery towards efficient downstream microbial conversion into value-added products. Additionally, comparative analysis of reported studies identifies the gaps encountered in bioprocess development and optimization, and highlights the opportunities for process integration and waste valorization. Beyond the bioprocessing stage, logistical constraints surrounding BP characteristics, decentralized availability, and transportation inefficiencies were summarized. Potential mitigation strategies such as localized biorefinery hubs, preprocessing, and integrated supply chain networks were critically discussed as pathways to improve substrate availability and process economics. Finally, the review outlines future prospects to integrate BP-based systems into circular bioeconomy models by coupling waste-based pretreatment optimization with value-added product recovery and sustainable logistics planning
Blue Carbon at the southern tip of Africa: current knowledge and future perspectives for dynamic estuarine environments
No full textBlue Carbon Ecosystems (BCEs), specifically salt marsh, seagrass, mangroves, occur in South Africa's relatively small, sheltered estuaries that are often disconnected from the ocean. These are dynamic environments where shifts between BCEs and other habitats along ecotones occur in response to mouth changes, floods and droughts, as well as anthropogenic pressures. Although Blue Carbon is becoming well established in South Africa, critical knowledge gaps remain; these are summarised under seven themes and future research and management actions identified. A holistic approach is recommended for Blue Carbon studies in estuaries to measure across elevation gradients (rather than focusing on individual vegetation types) and to include reeds, sedges and forested wetlands. Additionally, quantifying data deficient carbon stocks and processes, modelling future climate change impacts, instilling a sustainable long-term monitoring program, incorporating relevant emerging blue carbon stocks, realizing nationally inclusive restoration and protection co-management plans, and aligning local approaches with global frameworks of reporting are advocated as future recommendations with respect to South African BCEs. South Africa has high biodiversity and unique pressures influencing BCEs and is well positioned to inform the global research agenda. While the limited spatial extent of BCEs restricts the feasibility of carbon credit opportunities, high biodiversity values of these ecosystems hold potential under emerging ‘nature credit’ frameworks
Short-term effects of cover crop species and termination methods on soil ph and key enzymatic activities (β-glucosidase, phosphatase and urease activities) in a citrus orchard (eureka lemons)
No full textThe best management practices for cover cropping in citrus orchards, particularly in terms of species selection and termination methods, remain unclear. This study assessed the short-term effects of different cover crop species (vetch, medics and oats) and termination methods (slashed vs. non-slashed) on soil pH and enzyme activities (β-glucosidase, acid phosphatase, and urease) in a citrus orchard with sandy soil. A randomized complete block design with a factorial treatment structure and six replications was used. Soil samples were collected before and one year after cover crop establishment. The results showed that cover cropping increased soil pH from 5.42 to 6.00 after one year. However, no statistically significant differences were observed in soil pH or enzyme activities among cover crop species or termination methods. Marginal increases in enzyme activities were observed under leguminous cover crops, and these changes were insufficient to indicate strong treatment effects. Correlation and principal component analyses revealed that soil enzyme activities were more strongly influenced by soil properties (depth, carbon content and moisture) than by cover crop species or termination methods. These findings suggest that, under sandy soil conditions and within a one-year period, cover cropping has limited immediate effects on soil biological indicators in citrus orchards. Longer-term studies are recommended to assess cumulative impact
Cultivating communities: understanding motivations in urban gardening among low-income residents in Cape Town, South Africa
No full textIn local food systems research, a notable gap exists in exploring the personal motivations of individual gardeners, with most studies focusing solely on the overarching objectives of community gardens in Global South regions. This study bridges the gap by investigating the multifaceted motivations driving urban gardening among low-income residents in Cape Town’s Cape Flats, using a mixed-methods approach that integrates survey data from 97 participants and semi-structured interviews conducted across 34 community gardens. Although community gardens are predominantly designed with economic aims as evidenced by 29 out of 34 gardens prioritizing income generation, the findings reveal a tension between these institutional objectives and the personal motivations of individual gardeners. Quantitative analysis of the responses indicates that while 76.3% of participants indicated economic reasons, all respondents affirmed the importance of social, health, and environmental benefits. Qualitative insights further reveal that many gardeners perceive their participation as a means to enhance physical and psychological well‐being and to promote sustainable environmental practices, despite facing structural barriers such as limited space, time constraints, and inadequate resources. This study contributes to urban food systems literature by challenging conventional economic framings of urban gardening in the Global South and advocating for inclusive policies that bridge the gap between institutional aims and individual experiences, thereby enhancing the resilience and sustainability of urban community gardens