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We consider model-free monitoring procedures for strict stationarity of a given time series. The new criteria are formulated as L2-type statistics incorporating the multivariate empirical characteristic function. Asymptotic results are obtained for the closed-end scenario and Monte Carlo results are presented. The new methods are also employed in order to test for possible stationarity breaks in time-series data from the financial sector. © 2021 Elsevier Inc.

MSc (Research Psychology), North-West University, Potchefstroom Campus Africa is predicted to have an elderly population nearly double the current figures by 2050 (Reyers, 2018). Despite the increasing number of elderly people within the population, very little qualitative research could be found on what successful retirement entails for black South Africans. Quantitative studies have mostly focused on financial literacy and determining the financial readiness of South Africans with regards to retirement. However, elderly South Africans face numerous challenges such as poverty, lack of access to basic services, lack of quality medical care, that contribute to the lack of preparedness for retirement. The purpose of this study was to qualitatively explore how older black South Africans perceive successful retirement. A qualitative descriptive design was used with focus group interviews involving 12 participants within the Emfuleni Local Municipality near Vanderbijlpark. The study made use of purposive criterion sampling to identify the 12 participants. Four themes were identified through thematic analysis, namely: 1) financial freedom; 2) physical health; 3) community support base; and 4) educated children. Financial freedom included being able to buy necessities and being able to afford quality health care. Physical health was also important to te eldery to remain happy and able to engage with peers in various activities at the community centre. The community centre was highlighted as being an important source of support for the elderly. Lastly, the edlerly emphasised the importance of sending their children to be educated, in order for them to have successful lives and not be reliant on their parents. Future research into the perspectives of black South Africans could identify possible programs to promote successful retirement for black South Africans . Masters

We consider a model whereby a given response variable Y following a transformation Y: = T(Y) , satisfies some classical regression equation. In this transformation model the form of the transformation is specified analytically but incorporates an unknown transformation parameter. We develop testing procedures for the null hypothesis of homoskedasticity for versions of this model where the regression function is considered either known or unknown. The test statistics are formulated on the basis of Fourier-type conditional contrasts of a variance computed under the null hypothesis against the same quantity computed under alternatives. The limit null distribution of the test statistic is studied, as well as the behaviour of the test criterion under alternatives. Since the limit null distribution is complicated, a bootstrap version is suggested in order to actually carry out the test procedures. Monte Carlo results are included that illustrate the finite-sample properties of the new method. The applicability of the new tests on real data is also illustrated. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.

Background: Routine services for tuberculosis (TB) are being disrupted by stringent lockdowns against the novel SARS-CoV-2 virus. We sought to estimate the potential long-term epidemiological impact of such disruptions on TB burden in high-burden countries, and how this negative impact could be mitigated. Methods: We adapted mathematical models of TB transmission in three high-burden countries (India, Kenya and Ukraine) to incorporate lockdown-associated disruptions in the TB care cascade. The anticipated level of disruption reflected consensus from a rapid expert consultation. We modelled the impact of these disruptions on TB incidence and mortality over the next five years, and also considered potential interventions to curtail this impact. Results: Even temporary disruptions can cause long-term increases in TB incidence and mortality. We estimated that a 3-month lockdown, followed by 10 months to restore normal TB services, would cause, over the next 5 years, an additional 1.65 million TB cases (Crl 1.49– 1.85) and 438,000 TB deaths (CrI 403 – 483 thousand) in India, 41,400 (28,900–62,200) TB cases and 14,800 deaths (10.5 – 19.2 thousand) in Kenya, and 7,960 (6,250 – 9,880) cases and 2,050 deaths (1,610 - 2,360) in Ukraine. However, any such negative impacts could be averted through supplementary “catch-up” TB case detection and treatment, once restrictions are eased. Interpretation: Lockdown-related disruptions can cause long-lasting increases in TB burden, but these negative effects can be mitigated with targeted interventions implemented rapidly once lockdowns are lifted. Funding Statement: USAID and Stop TB Partnership. Declaration of Interests: The authors declare no conflict of interest.

There exist a number of tests for assessing the nonparametric heteroskedastic location-scale assumption. The goodness-of-fit tests considered are for the more general hypothesis of the validity of this model under a parametric functional transformation on the response variable, specifically testing for independence between the regressors and the errors in a model where the transformed response is just a location/scale shift of the error is considered. The proposed criteria use the familiar factorization property of the joint characteristic function under independence. The difficulty is that the errors are unobserved and hence one needs to employ properly estimated residuals in their place. The limit distribution of the test statistics is studied under the null hypothesis as well as under alternatives, and also a resampling procedure is suggested in order to approximate the critical values of the tests. This resampling is subsequently employed in a series of Monte Carlo experiments that illustrate the finite-sample properties of the new test. The performance of related test statistics for normality and symmetry of errors is also investigated, and application of our methods on real data sets is provided. © 2019 Elsevier B.V.

BACKGROUND: Proximal femoral insufficiency fractures are increasingly common in the elderly population. Urinary tract infection (UTI) is the most common associated complication in this group of patients with these injuries and may add to an already severe morbidity and mortality. The incidence of patients presenting with an established UTI from home is unknown as most research focuses on UTIs that occur after hospital admission. The aim of the study was to determine the prevalence of UTIs on admission and to compare urine culture results and patient profiles of these patients. METHODS: Forty patients presenting with a proximal femoral insufficiency fracture were identified on admission to casualty. A urine specimen was taken according to a standard protocol and sent for microscopy, culture and sensitivity (MCS). The organism and sensitivity profiles were determined from all positive MCS samples. Risk factors and patient demographics were identified using a questionnaire. RESULTS: Twenty of the 40 patients (50%) had a positive culture from the urine MCS. The most common organism was Escherichia coli (55%) [CI = 33.2; 76.8%] and the most common antibiotic sensitivity was to amoxicillin/clavulanic acid. Most of the organisms identified were resistant to ampicillin/amoxicillin and trimethoprim/sulfamethoxazole. Significant risk factors associated with an increased prevalence were female sex and the age of the patient. CONCLUSION: The prevalence of UTI in elderly patients with proximal femoral fractures is underestimated. Higher risk patients for presenting with a UTI from home are the elderly female patients above 80 years of age. Screening for, diagnosing and treating UTIs earlier has clear benefits for this specific group of patients to potentially decrease overall morbidity and mortality. LEVEL OF EVIDENCE: Level 4.

Highlights • Participants reported high levels of perceived stigma. • A moderate significant inverse correlation was observed between HRQoL and stigma. • Stigma was associated with seizure worry, emotional wellbeing and social functioning HRQoL domains. • Participants in employment or education had significantly better HRQoL than those who were not., Purpose People with non-epileptic seizures (NES) consistently report poorer Health-Related Quality of Life (HRQoL) than people with epilepsy. Yet, unlike in epilepsy, knowledge of how social factors influence the HRQoL of adults with NES is limited. To add to the evidence base, this study explores the relationship between HRQoL and perceived stigma among adults with NES, and the role of socio-demographic characteristics. Methods Data was gathered from a survey of 115 people living with the condition, recruited from online support groups. Participants provided socio-demographic and health-related data and completed a series of questions investigating their HRQoL (QOLIE-31) and stigma perceptions (10-item Epilepsy Stigma Scale). Results Participants were found to experience high levels of perceived stigma (median 5.2, mean 4.9). A significant and moderate inverse correlation was observed between HRQoL and stigma (rs − 0.474, p =

Patterns of egg deposition and rates of egg development were examined for two endemic South African scyliorhinid shark species: Poroderma pantherinum, the leopard catshark, and Haploblepharus pictus, the dark shy shark. P. pantherinum laid their eggs at an average depth of 18.95 m (min: 7.4 m; max: : 26.8 m) preferentially attaching their eggs singly onto sea fans Leptogorgia palma, Eunicella papillosa and Eunicella tricoronata. H. pictus laid their eggs at an average depth 3m(min: 1m; max: 30.7 m) and attached their eggs, predominantly in pairs, to the seaweed Bifurcariopis capensis. The average temperature at which eggs were found were similar (15°C) and eggs were laid year-round. Embryo development was observed in the laboratory under constant controlled environmental conditions of 14 and 17°C. Embryo length–age relationships were linear for both species and there were significant differences in growth rate at the two temperatures. For P. pantherinum average growth rate was 0.37 mm/day at 14°C and 0.79 mm/day at 17°C. The average incubation period was 266 days at 14°C and 125 days at 17°C. Embryos thus grew two times faster and development time was 53% shorter when the temperature was raised by only 3°C. For H. pictus, the average growth rate was 0.49 mm/day at 14°C and 0.78 mm/day at 17°C. The incubation period was 242 days at 14°C and 190 days at 17°C. The embryos thus grew 1.6 times faster and incubation time was 21.5% shorter when temperature was raised by only 3°C.Key words: elasmobranchs, reproduction, egg laying, egg development, South Africa.

Inflation is a far from homogeneous phenomenon, but this fact is ignored in most work on consumer price inflation. Using a novel methodology grounded in theory, the ten sub-components of the consumer price index (excluding mortgage interest rates, or CPIX) for South Africa are modeled separately and forecast, four quarters ahead. The method combines equilibrium correction models in a rich multivariate form with the use of stochastic trends estimated by the Kalman filter to capture structural breaks and institutional change. This research is of considerable practical use for monetary policy, allowing sectoral sources of inflation to be identified. Aggregating the forecasts of the components with appropriate weights from the overall index, potentially indicates the gains to be made in forecasting the idiosyncratic sectoral behaviour of prices, over forecasting the overall consumer price index.

MA (Communication Studies), North-West University, Potchefstroom Campus, 2016 The establishment of the NWU: a journalistic history is an inter-disciplinary study incorporating journalism and historiography. The background to this study as it evolved from an initial corporate history-writing project to a dissertation within a journalistic history-writing context, is described in Part 1. The outcome of the prime historiographical research is found in Part 2 and is also earmarked to be published as a popular history titled Forging unity: The story of the North-West University’s first years. The to-be-published book is therefore reproduced here as it will appear, albeit in monochrome. (A full-colour digital version is also provided.) Part 2 explains how the merger between the Potchefstroom University for Christian Higher Education and the University of North-West took place, as well as the incorporation of the Sebokeng Campus of Vista University into the Vaal Triangle Campus and the subsequent birth, integration and consolidation of the North-West University (NWU). As an interdisciplinary study theoretical orientations from both journalism and historiography anchored the research. In terms of journalism the phenomenological and sociocultural traditions, provided entry points into the study through organizational culture theory as well as ethnography and branching into institutional ethnography. Cultural history provided two approaches which served as theoretical under-pinnings for the historiography. They are the history of mentalities (which has been interpreted as the study of the emotions, feelings and attitudes associated with the theme at a specific time), but also the history of the present, whereby history is accepted as a device to understand the historical present. The study was done qualitatively in accordance with a flexible research design. A wide variety of primary and secondary sources, in particular oral history, served as the basis for the narrative. The study showed that the empirical and methodological overlap between historiography and journalism – which is not without its challenges – enabled the writing of a journalistic history of the establishment and first years of the NWU. The writing of a journalistic history of the NWU as a corporation posed difficulties. This stems from the clash between journalistic independence, as per the sociocultural tradition of the profession, and the organisational culture of corporations, which tend to shy away from history writing that would undermine their reputations. These challenges are addressed openly and discussed in Part 3. Masters

Objectives: Reliable estimates of the joint burden of HIV and tuberculosis epidemics\ud are crucial to planning strategic global and national tuberculosis responses. Prior to the\ud Global Tuberculosis Report 2013, the Global Tuberculosis Programme (GTB) released\ud estimates for tuberculosis–HIV incidence at the global level only. Neither GTB nor\ud United Nations Programme on HIV/AIDS (UNAIDS) published country specific estimates\ud for tuberculosis–HIV mortality. We used a regression approach that combined all\ud available data from GTB and UNAIDS in order to estimate tuberculosis–HIV incidence\ud and mortality at country level.\ud \ud Methods: A regression method was devised to relate CD4 dynamics (based on national\ud Spectrum files) to an increased relative risk (RR) of tuberculosis disease. The objective\ud function is based on least squares and incorporates all available country-level estimates\ud of tuberculosis–HIV incidence. Global regression parameters, obtained from\ud averaging results over countries with population survey estimates for tuberculosis–\ud HIV burden, were applied to countries with no survey tuberculosis–HIV incidence\ud estimates.\ud \ud Results: The method produced results that are in reasonably close agreement with\ud existing GTB estimates for global tuberculosis–HIV burden. It estimated that tuberculosis–HIV\ud accounts for 12.6% of global tuberculosis incidence, 21.3% of all tuberculosis\ud deaths, and 20% of all HIV deaths as estimated by the Spectrum AIDS Impact\ud Module (AIM). Regional estimates show the highest absolute incidence burden in East\ud and Southeast Asia, and the highest per capita burden in sub-Saharan Africa, where\ud between 12.5% (Central sub-Saharan Africa) and 60.6% (Southern sub-Saharan Africa)\ud of all tuberculosis disease occurs in people living with HIV (PLWH). Tuberculosis\ud mortality follows a similar pattern, except that a disproportionate percentage of global\ud tuberculosis deaths (12.1%) relative to global incidence (8.7%) occurred in Southern\ud sub-Saharan Africa.\ud \ud Conclusion: The disaggregation of tuberculosis incidence using a regression method on\ud RR of tuberculosis disease and all available data on HIV burden (from UNAIDS) and\ud tuberculosis–HIV testing (survey, sentinel and routine surveillance data) produces\ud results that closely match GTB estimates for 2011. The tuberculosis–HIV incidence\ud and mortality results were published in the Global Tuberculosis Report 2013. Several\ud limitations of and potential improvements to the process are suggested.

In Slip Knot Investments v Du Toit 2011 4 SA 72 (SCA) the Supreme Court of Appeal had to determine if the material mistake of a contractual party induced by the fraud of an independent third party could sustain a plea of iustus error raised by the mistaken party. The position prior to this decision was uncertain and characterised by inconsistency, mostly occasioned by the application of the iustus error doctrine together with fault. The Supreme Court of Appeal found that in the circumstances the mistaken party was liable, despite the fraud of the third party, on the basis of the reliance theory. The decision is commendable for bringing a measure of certainty to the law of mistake on this point and indicating that the reliance theory (as opposed to the iustus error doctrine) is the appropriate means to resolving such cases. Nevertheless, it is suggested that although the general rule implied by the court's approach is entirely apposite, there may well be exceptional instances where on the basis of relevant policy considerations the reliance theory should not prevail and the mistaken party should be absolved from contractual liability. In this manner reliance, which at first seems reasonable for being induced by the conduct of the contract denier, may upon further reflection be regarded as unreasonable based on the consideration of risk creation at the hand of the contract assertor, for instance. Admitting exceptions in appropriate circumstances would also provide a degree of consonance with earlier case law, where, even if the court's approach was open to theoretical criticism, a court has intuitively felt that liability should not lie.KEYWORDS: Third-party fraud; material mistake; iustus error doctrine; reliance theory; misrepresentation; reasonable reliance; suretyship; caveat subscriptor

In Slip Knot Investments v Du Toit 2011 4 SA 72 (SCA) the Supreme Court of Appeal had to determine if the material mistake of a contractual party induced by the fraud of an independent third party could sustain a plea of iustus error raised by the mistaken party. The position prior to this decision was uncertain and characterised by inconsistency, mostly occasioned by the application of the iustus error doctrine together with fault. The Supreme Court of Appeal found that in the circumstances the mistaken party was liable, despite the fraud of the third party, on the basis of the reliance theory. The decision is commendable for bringing a measure of certainty to the law of mistake on this point and indicating that the reliance theory (as opposed to the iustus error doctrine) is the appropriate means to resolving such cases. Nevertheless, it is suggested that although the general rule implied by the court's approach is entirely apposite, there may well be exceptional instances where on the basis of relevant policy considerations the reliance theory should not prevail and the mistaken party should be absolved from contractual liability. In this manner reliance, which at first seems reasonable for being induced by the conduct of the contract denier, may upon further reflection be regarded as unreasonable based on the consideration of risk creation at the hand of the contract assertor, for instance. Admitting exceptions in appropriate circumstances would also provide a degree of consonance with earlier case law, where, even if the court's approach was open to theoretical criticism, a court has intuitively felt that liability should not lie.

A simple mathematical model (Granich et al., Lancet 373:48-57, 2009) suggested recently that annual HIV testing of the population, with all detected HIV+ individuals immediately treated with antiretrovirals, could lead to the long-term decline of HIV in South Africa and could save millions of lives in the next few years. However, the model suggested that the long-term decline of HIV could not be achieved with less frequent HIV testing. Many observers argued that an annual testing rate was very difficult in practice. Small scale trials are nevertheless in preparation. In this paper, we use a more realistic age-structured model, which suggests that the recent high levels of reported condom use could already lead to a long-term decline of HIV in South Africa. The model therefore suggests that trials with for example 20% of the population tested each year would also be interesting. They would have similar (though smaller) advantages in terms of reduction of mortality and incidence, would be much easier to generalize to larger populations, and would not lead to long term persistence of HIV. Our model simulations also suggest that the age distribution of incidence has changed considerably over the past 20 years in South Africa. This raises some concern about an assumption presently used in EPP/Spectrum, the software used by UNAIDS for its estimates.