UWCScholar
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Persistent pharmaceuticals in a South African urban estuary and bioaccumulation in endobenthic sandprawns (Kraussillichirus kraussi)
(Multidisciplinary Digital Publishing Institute (MDPI), 2025) Petrik, Leslie; Murgatroyd, Olivia; Ojemaye, Cecilia
Pharmaceuticals are increasingly being detected in coastal ecosystems globally, but contamination and bioaccumulation levels are understudied in temporarily closed estuaries. In these systems, limited freshwater inputs and periodic closure may predispose them to pharmaceutical accumulation. We quantified in situ water column pharmaceutical levels at five sites in a temporarily closed model urban estuary (Zandvlei Estuary) in Cape Town, South Africa, that has been heavily anthropogenically modified. The results indicate an almost 100-fold greater concentration of pharmaceuticals in the estuary relative to False Bay, into which the estuary discharges, with acetaminophen (max: 2.531 µg/L) and sulfamethoxazole (max: 0.138 µg/L) being the primary pollutants. Acetaminophen was potentially bioaccumulative, while nevirapine, carbamazepine and sulfamethoxazole were bioaccumulated (BAF > 5000 L/kg) by sandprawns (Kraussillichirus kraussi), which are key coastal endobenthic ecosystem engineers in southern Africa. The assimilative capacity of temporarily closed estuarine environments may be adversely impacted by wastewater discharges that contain diverse pharmaceuticals, based upon the high bioaccumulation detected in key benthic engineers.
Perceived accuracy and utilisation of DHIS2 data for health decision making and advocacy in Kenya: a qualitative study
(Public Library of Science, 2025) Oware, Phoene Mesa; Omondi, Gregory; Adipo, Celestine
Reliable health information systems (HIS) are critical for effective decision-making in the delivery of Primary Health Care and Reproductive, Maternal, Newborn, Child, Adolescent Health and Nutrition (PHC/RMNCAH+N) services. In Kenya, the District Health Information Software 2 (DHIS2) platform serves as the primary HIS for tracking health indicators. This qualitative study explored perceptions of DHIS2 data accuracy and use for decision-making among PHC/RMNCAH+N stakeholders across 15 counties in Kenya. 89 Key Informant Interviews were conducted with PHC/ RMNCAH+N stakeholders, to explore experiences, barriers, and facilitators of DHIS2 data use. Thematic network analysis was employed to identify recurrent themes and generate insights into the utility of DHIS2-generated information. Sociotechnical challenges included limited technical capacity among health staff, inadequate analytical skills, and reliance on a small pool of Health Records Information Officers (HRIOs). However, positive practices emerged, such as the use of DHIS2 dashboards and user-friendly outputs, which were valued for supporting evidence-based decision-making and advocacy, particularly at higher levels of health management. In some counties, visual displays of data, including scorecards and performance trends, facilitated budget advocacy and community engagement. Contextual challenges and constraints, such as use of inconsistent data collection tools across counties post-devolution, human resource shortages, and limited integration of private sector data, contributed to incomplete reporting. These challenges underpinned perceived inaccuracy of DHIS2 data, arguably, hindering the complete reliance on DHIS2 data for planning and decision making. The study highlights the need for targeted investments to improve DHIS2 data accuracy and use through stronger stakeholder coordination, enhanced data synthesis skills, and fostering a culture of data ownership among a wide range of stakeholders in health, including political actors.. Addressing these gaps will contribute to improvement in DHIS2 data quality, enhanced ownership and reliance on DHIS2 data by PHC/RMNCAH+N stakeholders for decision making in Kenya.
Squeezing information from radio surveys to probe the primordial universe
(Institute of Physics, 2025) Karagiannis, Dionysios; Fonseca, José; Camera, Stefano; Clarkson, Chris
A major goal of cosmology is to understand the nature of the field(s) which drove primordial Inflation. Through future observations, the statistics of large-scale structure will allow us to probe primordial non-Gaussianity of the curvature perturbation at the end of Inflation. We show how a new correlation statistic can significantly improve these constraints over conventional methods. Next-generation radio telescope arrays are under construction which will map the density field of neutral hydrogen to high redshifts. These telescopes can operate as an interferometer, able to probe small scales, or as a collection of single dishes, combining signals to map the large scales. We show how to fuse these operating modes in order to measure the squeezed bispectrum with higher precision and greater economy. This leads to constraints on primordial non-Gaussianity that will improve on measurements by Planck, and out-perform other surveys such as Euclid. We forecast that σ(f NLloc)∼ 3, achieved by using a small subset, O(102 - 103), of the total number of accessible triangles. The proposed method identifies a low instrumental noise, systematic-free scale regime, enabling clean squeezed bispectrum measurements. This provides a pristine window into local primordial non-Gaussianity, allowing tight constraints not only on primordial non-Gaussianity, but on any observable that peaks in squeezed configurations.
Investigating the earnings of migrant and local day labourers in Johannesburg, South Africa—a post-Covid-19 perspective
(John Wiley and Sons Ltd, 2025) Schenck, Catherina; Blaauw, Derick; Pretorius, Anmar
The 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.
Aspects relevant for nucleosynthesis in novae and 136Xe neutrinoless double beta decay, probed via 32S(d; t) and 137Ba(3He; ) reactions
(University of the Western Cape, 2025) Kamil, Mohamed
This work uses two independent neutron removal reactions to investigate nuclear states relevant for two contexts: the 30P(p; )31S resonance reaction, which plays a crucial role in nucleosynthesis pathways in novae, and the neutrinoless double beta decay (0 ) of 136Xe ! 136Ba. To achieve these objectives, high-resolution measurements using the 32S(d; t) and the 137Ba(3He; ) reactions were employed to probe excitation energies of interest in 31S and 136Ba, respectively. Both experiments were performed using the Q3D spectrograph at the Maier-Leibnitz Laboratory (MLL) in Garching, Germany. A rigorous statistical analysis of the 32S(d; t) data was used to resolve a discrepancy concerning the existence of an astrophysically relevant state in 31S at around 6.4 MeV. The analysis of the second dataset provided valuable spectroscopic information to test calculated matrix elements for 136Xe 0 .