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On the relationship between the cosmic web and the alignment of galaxies and AGN jets
No full textThe impact of active galactic nuclei (AGNs) on the evolution of galaxies explains the steep decrease in the number density of the most massive galaxies in the Universe. However, the fuelling of the AGN and the efficiency of this feedback largely depend on their environment. We use data from the Low Frequency Array Two-metre Sky Survey Data Release 2 (DR2), the Dark Energy Spectroscopic Instrument Legacy Imaging Surveys, and the Sloan Digital Sky Survey DR12 to make the first study of the orientations of radio jets and their optical counterpart in relation to the cosmic web environment. We find that close to filaments (≲11 Mpc), galaxies tend to have their optical major axes aligned with the nearest filaments. On the other hand, radio jets, which are generally aligned perpendicularly to the optical major axis of the host galaxy, show more randomized orientations with respect to host galaxies within ≲8 Mpc of filaments. These results support the scenario that massive galaxies in cosmic filaments grow by numerous mergers directed along the orientation of the filaments while experiencing chaotic accretion of gas on to the central black hole. The AGN-driven jets consequently have a strong impact preferentially along the minor axes of dark matter haloes within filaments. We discuss the implications of these results for large-scale radio jet alignments, intrinsic alignments between galaxies, and the azimuthal anisotropy of the distribution of circumgalactic medium and anisotropic quenching
Investigating the earnings of migrant and local day labourers in Johannesburg, South Africa—a post-Covid-19 perspective
No full textThe fallout of the Covid-19 pandemic exacerbated the already challenging conditions prevailing among the day labourers in South Africa. We investigated the labour market outcomes (especially income) of day labourers after the Covid-19 pandemic by focusing on day labourers, both local and foreign, in Johannesburg, South Africa. The methodology for our investigation was based on protocols used in other international and South African studies on various aspects pertaining to day labouring in the Global North and Global South. The fieldwork was carried out in the second half of 2021—completing 241 structured interviews. Regression results indicate that, in general, day labourers' experience and ability to negotiate their wages before accepting a job are the main determinants of their income. Site size matters more for migrants compared to locals, while performing a highly skilled job matters more for local South Africans. Since the bargaining position of workers in the informal economy continues to be eroded in the aftermath of the Covid-19 pandemic, day labourers may be especially affected, and their structural vulnerability may worsen—and even more so for the migrants
From Google translate to ChatGPT: the use of large language models in translating, editing, and revising
No full textThis chapter examines the quality of machine translated texts of various genres with a view to finding out to what extent these texts/genres have been accurately translated by neural machine translation systems and LLMs. The chapter also examines the potential use of these technologies in editing and revisions to enhance both quality and productivity. A theoretical and conceptual framework that is based on text-typology linguistic models and Mossop's parameters of revising and editing in translation is used to assess the quality of transactions produced by Google Translate (GT) as a neural-based machine translation system and ChatGPT as a large language model (LLM). In particular, the chapter investigates the GT and ChatGPT translations of argumentation within journalistic texts, exposition within both promotional and philosophical genres, and instrumental texts within the legal genre. This emphasis on diverse text types allows for a comprehensive evaluation of the translation performance of neural-based systems and LLMs across different communicative purposes and stylistic demands
A nano-ag/urease/urea signal-amplification platform Towards nano-enzymatically enabled ionoamperometric Genosensor procedure
No full textThe rising occurrence of tropical neglected diseases and the fast spread of viral infections emphasizes the need for the development of rapid, accurate, selective, sensitive, and cheap analytical devices such as genosensors (biosensors) for early diagnosis in the point of cares (PoC) as per the world health organization (WHO) recommendations. Toward the development of the first iono-amperometric nanoenzymatically amplified sandwich RNA-genosensors, electrochemical sensor platforms for urea based on a seldom employed electrochemical transduction technique, traditionally known as ion transfer voltammetry at the interface between two immiscible electrolyte solutions (ITIES), were constructed and characterized as follows. An NH4+ ion sensor was assembled according to literature by placing a hydrophobic electrolyte phase (O-phase) containing dibenzo-18-crown-6 (DB18C6, 50mM), an NH4+-selective ionophore (selectophore), and ethyl-violet tetraphenylborate (EthVTPB, 10 mM), in a teflon tube, the end of which was sealed with semi-permeable cellulose membrane (CM)
Rangeland conditions and grazing capacities on livestock farms during and after drought in three biomes in South Africa
No full textClimate change has intensified extreme weather events worldwide, such as droughts, which have severely affected South Africa’s rangelands by reducing productivity and increasing livestock mortality. This study aimed to investigate variability in grazing capacities and stocking rates with respect to land tenure, long-term grazing capacity norms, field surveys, and farmer perceptions during and post-drought conditions in the three biomes in South Africa. In-person interviews and field surveys were conducted with 85 farmers from the Grassland (n = 25), Savanna (n = 35), and Nama-Karoo (n = 30) biomes and vegetation condition was surveyed during or after the drought. Grazing capacity did not differ significantly across land tenure systems in the Savanna biomes (p > 0.05), but significant differences were found in the Grassland and Nama-Karoo biomes (p 60% of farmers in the Nama-Karoo biome rated their rangeland condition as poor because of the drought, and field surveys showed that grazing capacities were four times lower than the national recommended grazing capacity norm. Considering the high inter-annual variability in vegetation productivity and differences in farmers’ perceptions based on local knowledge, it is recommended that the Department of Agriculture adopt flexible grazing capacity ranges in the regulations of the Conservation of Agricultural Resource Act 43 of 1983
Advancement in electrochemical sensing of chloramphenicol in varying matrixes: a review
No full textChloramphenicol (CAP) have demonstrated its broad effectiveness against bacterial infections. However, its persistence in the environment and potential toxicity led to strict global regulations limiting its use. As a result, rapid and accurate detection methods for CAP are being developed to protect public health and maintain regulatory compliance regarding its presence in the environment. Conventional analytical methods such as High-Performance Liquid Chromatography, Gas Chromatography, and Liquid Chromatography–Mass Spectrometry were commonly used for CAP detection. However, these conventional methods suffer challenges such as time-consumption, fabrication complexity, reproducibility, and cost. With electrochemical sensing techniques presenting varying valuable benefits, such as instant detection, low power consumption, simultaneous analysis, and portability, making them essential for timely monitoring of various analytes. The performance of electrochemical sensor is further boosted by integrating materials such as spinels, metal oxides, and metallic nanoparticles. These materials are broadly investigated as electrode interface components thanks to their features that collectively boost electrochemical sensor such as providing excellent electrical conductivity, distinct catalytic behavior, and larger surface areas. Furthermore, this paper reviews the impact of traditional and standards analytical methods, as well as their recent advancement based on the detection of CAP in aqueous media
A comparison of the accuracy of fit of major connectors in conventional and digital partial denture frameworks: an in vitro study
No full textBackground: Premature loss of teeth has been attributed to numerous causes. Dentures are the most frequent form of oral rehabilitation approach to ensure the maintenance of function. Currently, dentures are either conventionally or digitally fabricated. Major connectors make up the key apparatuses of a removable partial denture (RPD), and the accuracy of the fit in a conventional and digitally fabricated RPD will impact not only its numerous functions but also the success of the removable partial denture. Aim: The aim of this study sought to compare the accuracy of fit of major connectors in conventional and digitally fabricated upper removable chrome-cobalt partial denture frameworks. Method: An in vitro research design was implemented for this study. This study was conducted on chrome-cobalt frameworks manufactured for a Kennedy class III maxillary RPD. There were two conventional and two digital groups. Ten frameworks were manufactured for each group, totalling 40 frameworks. 7 identified palatal landmarks were designated, namely: incisive papilla; left palatal rugae; left lateral gingiva; palatine raphe; posterior border; right lateral gingiva; and right palatal rugae. The accuracy of fit of the major connectors of each chrome cobalt framework was conducted by superimposing each framework on its respective model and measuring the accuracy of fit at the identified palatal landmarks
An analysis of aspects of the consumer protection framework for mobile money services in Zambia
No full textThis mini-dissertation examines the consumer protection framework for mobile money services in Zambia. It identifies gaps in the current framework and highlights areas for reform to strengthen consumer protection for mobile money users. Mobile money has played a key role in advancing financial inclusion in Zambia. However, its rapid growth has outpaced the development of adequate consumer protection measures, exposing users to potential exploitation and financial risks. The study adopts a qualitative research approach, using secondary data and legal sources to evaluate Zambia’s consumer protection framework for mobile money services. It highlights key gaps in financial education, dispute resolution mechanisms, transparency, and overlapping jurisdiction among regulators such as the Bank of Zambia (BoZ), the Zambia Information and Communication Technology Authority (ZICTA), and the Competition and Consumer Protection Commission (CCPC). Drawing lessons from South Africa’s Twin Peaks regulatory model and the Southern African Development Community (SADC) Mobile Money Guidelines, the mini-dissertation recommends adopting a principles-based regulatory framework, strengthening coordination among regulators, and establishing dedicated consumer protection measures such as an ombudsman for dispute resolution. Additionally, it emphasises the need for enhanced financial literacy programmes and standardised disclosure requirements to mitigate information asymmetry. In addressing these gaps, Zambia can institute a more secure, transparent, and inclusive mobile money ecosystem, aligning with international best practices and sustaining the benefits of digital financial services for its population
Perceptions of South Africa’s master of public health graduates on the degree’s contribution to their leadership at work and in society
No full textIntroduction: Integrating public health functions into national health systems is essential to enhance population health. The Master of Public Health (MPH) degree is an important foundation for public health practice in low-and middle-income countries such as South Africa. However, insufficient evidence on individual motivations for undertaking the MPH and the perceptions of graduates on the utility of the degree at work and in society and its contribution to their leadership skills informed this study. Methods: A consortium of academics from eight South African universities developed a self-administered questionnaire to measure inter alia the socio-demographic characteristics, motivations, career paths, perceptions of the utility of the degree, and its contribution to their professional and personal development. The study population comprised the 2012–2016 cohort of MPH graduates from eight universities. Following informed consent, eligible graduates completed an online survey via REDCap. The data were analyzed using Stata. Results: A total of 221 graduates completed the survey. The mean age of respondents was 35 years, and the majority were from South Africa (53.2%) or other African countries (43.2%). The majority (91.1%) completed the MPH to improve their skills or to promote their personal development for senior management and leadership roles. Approximately 75% used identified leadership skills at work, but only half these skills were obtained from the MPH. Over 80% of respondents positively impacted on their workplace and in society, using skills mostly derived from the MPH in all domains. Discussion: This cohort of MPH graduates exercised leadership in different settings, but many stated that these skills were not obtained from the MPH programs. The COVID-19 pandemic underscored the need for public health leaders skilled in communication, collaboration, and crisis management, amidst considerations of social justice and equity. Hence, leadership skills need to be intentionally included in MPH programs in South Africa
The global, regional, and national burden of cancer, 1990–2023, with forecasts to 2050: a systematic analysis for the Global Burden of Disease Study 2023
No full textBackground: Cancer is a leading cause of death globally. Accurate cancer burden information is crucial for policy planning, but many countries do not have up-to-date cancer surveillance data. To inform global cancer-control efforts, we used the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2023 framework to generate and analyse estimates of cancer burden for 47 cancer types or groupings by age, sex, and 204 countries and territories from 1990 to 2023, cancer burden attributable to selected risk factors from 1990 to 2023, and forecasted cancer burden up to 2050. Methods: Cancer estimation in GBD 2023 used data from population-based cancer registration systems, vital registration systems, and verbal autopsies. Cancer mortality was estimated using ensemble models, with incidence informed by mortality estimates and mortality-to-incidence ratios (MIRs). Prevalence estimates were generated from modelled survival estimates, then multiplied by disability weights to estimate years lived with disability (YLDs). Years of life lost (YLLs) were estimated by multiplying age-specific cancer deaths by the GBD standard life expectancy at the age of death. Disability-adjusted life-years (DALYs) were calculated as the sum of YLLs and YLDs. We used the GBD 2023 comparative risk assessment framework to estimate cancer burden attributable to 44 behavioural, environmental and occupational, and metabolic risk factors. To forecast cancer burden from 2024 to 2050, we used the GBD 2023 forecasting framework, which included forecasts of relevant risk factor exposures and used Socio-demographic Index as a covariate for forecasting the proportion of each cancer not affected by these risk factors. Progress towards the UN Sustainable Development Goal (SDG) target 3.4 aim to reduce non-communicable disease mortality by a third between 2015 and 2030 was estimated for cancer. Findings: In 2023, excluding non-melanoma skin cancers, there were 18·5 million (95% uncertainty interval 16·4 to 20·7) incident cases of cancer and 10·4 million (9·65 to 10·9) deaths, contributing to 271 million (255 to 285) DALYs globally. Of these, 57·9% (56·1 to 59·8) of incident cases and 65·8% (64·3 to 67·6) of cancer deaths occurred in low-income to upper-middle-income countries based on World Bank income group classifications. Cancer was the second leading cause of deaths globally in 2023 after cardiovascular diseases. There were 4·33 million (3·85 to 4·78) risk-attributable cancer deaths globally in 2023, comprising 41·7% (37·8 to 45·4) of all cancer deaths. Risk-attributable cancer deaths increased by 72·3% (57·1 to 86·8) from 1990 to 2023, whereas overall global cancer deaths increased by 74·3% (62·2 to 86·2) over the same period. The reference forecasts (the most likely future) estimate that in 2050 there will be 30·5 million (22·9 to 38·9) cases and 18·6 million (15·6 to 21·5) deaths from cancer globally, 60·7% (41·9 to 80·6) and 74·5% (50·1 to 104·2) increases from 2024, respectively. These forecasted increases in deaths are greater in low-income and middle-income countries (90·6% [61·0 to 127·0]) compared with high-income countries (42·8% [28·3 to 58·6]). Most of these increases are likely due to demographic changes, as age-standardised death rates are forecast to change by –5·6% (–12·8 to 4·6) between 2024 and 2050 globally. Between 2015 and 2030, the probability of dying due to cancer between the ages of 30 years and 70 years was forecasted to have a relative decrease of 6·5% (3·2 to 10·3). Interpretation: Cancer is a major contributor to global disease burden, with increasing numbers of cases and deaths forecasted up to 2050 and a disproportionate growth in burden in countries with scarce resources. The decline in age-standardised mortality rates from cancer is encouraging but insufficient to meet the SDG target set for 2030. Effectively and sustainably addressing cancer burden globally will require comprehensive national and international efforts that consider health systems and context in the development and implementation of cancer-control strategies across the continuum of prevention, diagnosis, and treatment. Funding: Gates Foundation, St Jude Children's Research Hospital, and St Baldrick's Foundation