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The Zondo Commission and the crisis of accountability in South Africa’s state-owned enterprises. the case of Eskom and state capture.
No full textThe 2016 State of Capture Report published by the former Public Protector Thuli Madonsela catalysed the establishment of the Zondo Commission. The Zondo Commission investigated allegations of state capture involving several South African state-owned enterprises (SOEs). The focus of this study was specifically on the Electricity Supply Commission (Eskom). The importance of this study stems from the reality that Eskom is one of the biggest SOEs in South Africa. Its apparent vulnerability casts a looming shadow over the future of quality, affordable energy supply. Eskom’s monopoly over energy supply in South Africa means its failure or malfunction has wider consequences for the public. The Public Protector's report highlighted incidents of bribery, fraud and corruption and also noted the severe lack of accountability and conflicts of interest involving several public officials in SOEs. These issues compounded the growing concern that anti-corruption measures had eroded and South Africa's SOEs were “captured”. This culminated in what was known as the Zondo Commission, which investigated allegations of state capture by putting several public officials under the microscope of public proceedings. Eskom was one of the SOEs subject to heavy criticism for its wasteful expenditure, questionable relationships, leadership failures and poor service delivery. This research sought to gain a deeper understanding of the effectiveness of the Zondo Commission inquiry of Eskom and the strength of accountability mechanisms
The structural, electrical and dielectric studies of CMC based biopolymer gel electrolytes for ecofriendly device applications
No full textThe solution casting procedure has been effectively used to synthesize biopolymer gel electrolytes (BGEs) using carboxymethyl cellulose (CMC) and ammonium thiocyanate (NH4SCN). The XRD patterns of the bio-based green emulsions (BGEs) have provided evidence of the non-crystalline structure of the films. Optical micrographs of BGEs have revealed the formation of homogeneous gel electrolyte films. Complex impedance spectroscopy has been used to investigate the ion transport mechanism and dielectric relaxation dynamics of biopolymer gel electrolyte films over a wide range of temperatures. The conductivity of the gel electrolyte samples has been shown to rise with the amount of salt present. The optimum ionic conductivity, determined at room temperature, is σ = 3.97 × 10−3 Scm−1, and it is achieved in the gel electrolyte sample containing 35 wt% NH4SCN. The variation in ionic conductivity with temperature has shown a blend of Arrhenius and Vogel-Tamman-Fulcher (VTF) characteristics. An analysis has been conducted on the impedance data to investigate the ion transport process using the formalisms of ac conductivity, permittivity, and electric modulus. The dielectric impedance of the BGEs films has been used to determine the charge carrier density and mobility. The electrolyte with the best conductivity has shown a broad range of electrochemical stability, spanning from −1.49 to +1.27 V. The I-t investigations has shown a high transference number (tion ~ 0.99), indicating that ions are the primary contributors to conductivity. The cyclic voltammetry tests have shown excellent reusability, indicating its potential use in devices, such as supercapacitors and rechargeable batteries
An evaluation of the potential radiosensitization effect of spherical gold nanoparticles to induce cellular damage using different radiation qualities
No full textGlobal disparities in cancer prevention, detection, and treatment demand a unified international effort to reduce the disease’s burden and improve outcomes. Despite advances in chemotherapy and radiotherapy, many tumors remain resistant to these treatments. Gold nanoparticles (AuNPs) have shown promise as radiosensitizers, enhancing the effectiveness of low-energy X-rays by emitting Auger electrons that cause localized cellular damage. In this study, spherical AuNPs of 5 nm and 10 nm were characterized and tested on various cell lines, including malignant breast cells (MCF-7), non-malignant cells (CHO-K1 and MCF-10A), and human lymphocytes. Cells were treated with AuNPs and irradiated with attenuated 6 megavoltage (MV) X-rays or p(66)/Be neutron radiation to assess DNA double-strand break (DSB) damage, cell viability, and cell cycle progression. The combination of AuNPs and neutron radiation induced higher levels of γ-H2AX foci and micronucleus formation compared to treatments with AuNPs or X-ray radiation alone. AuNPs alone reduced cellular kinetics and increased the accumulation of cells in the G2/M phase, suggesting a block of cell cycle progression. For cell proliferation, significant effects were only observed at the concentration of 50 μg/mL of AuNPs, while lower concentrations had no inhibitory effect. Further research is needed to quantify internalized AuNPs and correlate their concentration with the observed cellular effects to unravel the biological mechanisms of their radioenhancement
A fitted parameter convergent finite difference scheme for two-parameter singularly perturbed parabolic differential equations
No full textThe objective of this paper is to develop a numerical scheme that is uniform in its parameters for a specific type of time-dependent parabolic problem with two perturbation parameters. The existence of these two parameters in the terms with the highest-order derivatives results in the formation of boundary layer(s) in the solution of such problems. Solving these model problems using classical methods does not yield satisfactory results due to the layer behavior. Therefore, nonstandard finite difference schemes have been developed as a means to obtain numerical solutions for these problems. To develop the scheme, we employ the Crank-Nicolson discretization on a uniform time mesh and apply a fitted operator method with a uniform spatial mesh. We have established the stability and convergence of the proposed scheme. The proposed scheme exhibits uniform convergence of second order in the temporal direction and first order in the spatial direction. However, temporal mesh refinements is employed to enhance the order to two in both directions.. Model examples are provided to validate the practicality of the proposed numerical scheme
Does cooling affect skeletal muscle glycogen replenishment after an acute bout of fear-induced exertional hyperthermia in blesbok (damaliscus pygargus phillipsi)?
No full textRhabdomyolyses is a clinical sign of capture myopathy in wild animals and may be linked to glycogen metabolism. To study potential mechanisms, 26 wild blesbok were chased for 15 min and immobilised, whereafter 12 of these blesbok were doused with ice-water (n = 14 chased only group; n = 12 chased + cooled group). An additional 12 blesbok served as resting (not chased) uncooled controls. Vastus lateralis biopsies were obtained after immobilisation for biochemical analyses. Biopsies obtained at initial capture, 3- and 16-days post exercise were analysed for glycogen content. Blesbok muscles contained predominantly myosin heavy chain (MHC) IIA (∼50 ± 9 %), followed by IIX (32 ± 10 %) and MHC I (18 ± 5 %), with no difference between groups. Citrate synthase (mean: 87 ± 48), 3-hydroxyacetyl co A dehydrogenase (47 ± 17), lactate dehydrogenase (1567 ± 654), phosphorylase (162 ± 94), phosphofructokinase (250 ± 123) and creatine kinase (12,455 ± 6372) activities (in μmol/min/g prot) were not different between groups. Similarly, superoxide dismutase (7.9 ± 7 U/mg prot), catalase (8.8 ± 5.8 mmol/min/g prot), and overall antioxidant capacity (ORAC: 23055 ± 18,460 μmol/g prot) were not different between groups. Glycogen content was reduced in both chased groups and not replenished by day 3. Glycogen supercompensation was observed on day 16 in both chased groups (∼33 % higher than resting control group). The results confirm that blesbok have high muscle metabolic capacities, and that glycogen resynthesis is slow, which could lead to metabolite deficiency during prolonged chase events (>15 min)
UYSD: a novel data repository accessible via public website for worldwide population frequencies of Y-SNP haplogroups
No full textFor decades, there has been scientific interest in the variation and geographic distribution of paternal lineages associated with the human Y chromosome. However, the relevant data have been dispersed across numerous publications, making it difficult to consolidate. Additionally, understanding the relationships between different variants, and the tools used to analyze them, have evolved over time, further complicating efforts to harmonize this information. The Universal Y-SNP Database (UYSD) marks a substantial advancement by providing a comprehensive and accessible platform for Y-SNP and haplogroup data from populations around the world. UYSD harmonizes diverse datasets into a unified repository, facilitating the exploration of global Y-chromosomal variation. The platform handles data generated with both high- and low-throughput technology and is compatible with the automated analysis software tool, Yleaf v3. Key functionalities include the ability to: i) visualize haplogroup distributions on an interactive world map, ii) estimate haplogroup frequencies in geographic regions with sparse data through interpolation, and iii) display detailed phylogenetic trees of Y-chromosomal haplogroups. Currently, UYSD encompasses data from over 6,600 males across 27 populations. This dataset largely aligns with known global Y-haplogroup patterns, but also reveals unexplored finer-scale geographic variations. While the present dataset is largely European-centered, UYSD is designed for ongoing expansion by the scientific community, aiming to include more global data and higher-resolution population sequencing data. The platform thus offers valuable insights into human genetic diversity and migration patterns, serving several fields of research such as: human population genetics, genetic anthropology, ancient DNA analysis and forensic genetics
Modeling the population dynamics of HIV/AIDS with opportunistic infections at the severe stage of HIV
No full textIn this paper, we present a deterministic model for the population dynamics of HIV/AIDS, wherein some individuals at the severe symptomatic phase of HIV develop serious opportunistic infections (OIs) such cryptococcal, tuberculous, pneumococcal, and other bacterial meningitis due to an inappropriate treatment or lack of counseling. OIs are responsible for significant mortality and disability on individuals with HIV in many countries. Cryptococcal meningitis (CM) is among frequent OIs responsible for significant mortality and disability of individuals with HIV in limited resource settings. However, there are also cases of high mortality due to CM on HIV-uninfected individuals, but the burden of CM is more frequent in people living with HIV. We proved the global stability of the disease-free as well as the endemic equilibrium points. In addition, we performed the study of sensitivity analysis of the basic reproduction number with the parameters of the model as well as with some compartmental classes. We illustrated our theoretical results by way of numerical simulations using a projection on the HIV historical data of South Africa since 2024. Our analysis showed that a combination of ART and OI specific treatments may reduce the number of death related cases
Effect of calcination on morphology of zinc oxide nanoparticles
No full textZinc oxide (ZnO) nanoparticles are synthesized using the sol-gel method by considering zinc acetate dihydrate as a precursor, and the morphology and crystalline structure of the as-synthesized ZnO nanoparticles are understood using materials characterization techniques. The effect of calcination temperature and time on the morphology of ZnO powder is studied thoroughly and systematically. The recipe for preparing highly pure ZnO powders is optimized at minimal calcination temperature and time. The powder X-ray diffraction analysis reveals a wurtzite crystal structure for ZnO nanoparticles (ZnO-NPs). From the diffraction patterns, it is evident that the powders calcined at 700 °C for 3 h closely match the JCPDS standard for minimal calcination temperature and time. The peak at 364.48 cm−1 in the Fourier transform infrared spectroscopy provides information about the bonding interaction between Zn and O in ZnO-NPs. The UV-Visible absorption spectra of ZnO-NPs indicate a shifting of peak from 374.37 to 378.49 nm, and the corresponding Tauc plot estimates a change in band gap from 2.461 eV to 2.847 eV for ZnO prepared with calcined at 700 °C for 3 h and 6 h, respectively, due to change in morphology and particle size. The field emission scanning electron microscopy (FESEM) images indicate the formation of spherical-shaped nanoparticles with smooth surfaces and EDAX spectra reveal compositions of zinc and oxygen-only ZnO-NPs. Noticeable changes in the particle size and morphology are observed with increasing calcination temperature. The Raman spectra of the ZnO-NPs recorded using a 514 nm excitation wavelength indicate E2(high) mode at 437.5 cm−1 in Zno-NPs prepared by calcining at 700 °C for 3 h. The optimal condition for achieving high pure ZnO-NPs with well-defined morphology is concluded by calcining the ZnO powder at 700 °C for a duration of 3 h
Considering a single anti-corruption agency for South Africa
No full textIn recent years, concerns about corruption have increased in South Africa. Although corruption is widely discussed, less focus is placed on the anti-corruption agencies and their efficiency in countering corruption. These agencies are established in terms of legislation to prevent, combat, investigate and prosecute corruption in line with international and regional instruments and domestic legislation. Though the approach is a multiple-agency approach, over the years, some agencies were established, re-designed and others done away with. The question is whether the current anti-corruption agencies are still efficient in fighting corruption in line with international standards. The proposed standard is that ACAs should be independent, specialised, staffed, and have sufficient resources to meet their roles and responsibilities. The focus of this dissertation is to assess the efficiency of specific anti-corruption agencies in South Africa. This dissertation hopes to contribute to a better understanding of what a model anti-corruption agency is and how the agencies in South Africa measure against that model. The analysis looks at the mandate and discusses the strengths and weaknesses of the agencies. The strengths include the legal framework that provides the ACA with its mandate and powers and its independence and public collaboration. The weaknesses include political interference, insufficient legal framework and resources as well a lack of public trust. It is recommended that a single agency should be used in South Africa
A methodological assessment of randomization integrity in alteplase for acute ischemic stroke individual patient data meta-analyses
No full textObjectives Little is known about the integrity of randomization for randomized controlled trials (RCT) included in alteplase for stroke meta-analyses. If the RCTs were not properly randomized, the results could not be accepted at face value. The objective was to assess the integrity of randomization in individual patient data (IPD) meta-analyses supporting alteplase for acute ischemic stroke. Methods We assessed randomization reporting, performed qualitative risk of bias assessments arising from the randomization process, and performed fixed effects meta-analyses of baseline variables for which zero heterogeneity is expected if all included RCTs have unbiased randomization. Fixed-effects meta-analyses of baseline age, weight, and National Institute of Health Stroke Scale (NIHSS) score were performed. If heterogeneity was present (I2 > 0%), trials were systematically removed, starting with the RCT with the largest t-statistic until the I2 value was 0%. Results The NINDS rt-PA Stroke Study had a high risk of bias, the ECASS-3 RCT had some concerns, and all other trials were graded as low risk according to the Cochrane Risk of Bias (ROB-2) tool. The NINDS rt-PA Stroke Study contributed to heterogeneity in age and weight meta-analyses, and the ECASS-3 RCT contributed to heterogeneity in the NIHSS score meta-analysis. Removal of suspect trials resulted in the expected I2 value of 0%. Conclusions: The NINDS rt-PA Stroke Study and ECASS-3 trials contributed to heterogeneity in fixed effects meta-analyses of baseline variables while there should have been none. These RCTs are likely a source of selection bias in IPD meta-analyses due to suspect randomization