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TheAspergillusseriesNigricontains biotechnologically and medically important species. They can produce hazardous mycotoxins, which is relevant due to the frequent occurrence of these species on foodstuffs and in the indoor environment. The taxonomy of the series has undergone numerous rearrangements, and currently, there are 14 species accepted in the series, most of which are considered cryptic. Species-level identifications are, however, problematic or impossible for many isolates even when using DNA sequencing or MALDI-TOF mass spectrometry, indicating a possible problem in the definition of species limits or the presence of undescribed species diversity. To re-examine the species boundaries, we collected DNA sequences from three phylogenetic markers (benA,CaMandRPB2) for 276 strains from seriesNigriand generated 18 new whole-genome sequences. With the three- gene dataset, we employed phylogenetic methods based on the multispecies coalescence model, including four single-locus methods (GMYC, bGMYC, PTP and bPTP) and one multilocus method (STACEY). From a total of 15 methods and their various settings, 11 supported the recognition of only three species corresponding to the three main phylogenetic lineages:A. niger,A. tubingensisandA. brasiliensis. Similarly, recognition of these three species was supported by the GCPSR approach (Genealogical Concordance Phylogenetic Species Recognition) and analysis in DELINEATE software. We also showed that the phylogeny based onbenA,CaMandRPB2is suboptimal and displays significant differences from a phylogeny constructed using 5 752 single-copy orthologous proteins; therefore, the results of the delimitation methods may be subject to a higher than usual level of uncertainty. To overcome this, we randomly selected 200 genes from these genomes and performed ten independent STACEY analyses, each with 20 genes. All analyses supported the recognition of only one species in theA. nigerandA. brasiliensislineages, while one to four species were inconsistently delimited in theA. tubingensislineage. After considering all of these results and their practical implications, we propose that the revised seriesNigriincludes six species:A. brasiliensis,A. eucalypticola,A. luchuensis(syn. A. piperis),A. niger(syn.A. vinaceusandA. welwitschiae),A. tubingensis(syn.A. chiangmaiensis,A. costaricensis,A. neonigerandA. pseudopiperis) andA. vadensis. We also showed that the intraspecific genetic variability in the redefinedA. nigerandA. tubingensisdoes not deviate from that commonly found in other aspergilli. We supplemented the study with a list of accepted species, synonyms and unresolved names, some of which may threaten the stability of the current taxonomy. more...

As the world moves towards a net-zero future, different jurisdictions are considering various scenarios on how they can achieve their targets. Depending on the types of assets within each jurisdiction, it could mean the development of new projects, modifying existing infrastructure, or a combination of both. The Victorian Climate Change Act 2017 established a system of coordinated, whole-of-economy actions to achieve a net zero emissions target by 2050. This includes rolling 5-year plans and targets to reduce emissions and adapt to climate change impacts, obliging all government policies, plans and decisions to consider climate change, and requiring all sectors of the economy including the gas industry to develop and action emissions reduction pledges. Natural gas plays a major role in Victoria’s energy mix with extensive gas infrastructure supplying over 2 million customers in Victoria and a network asset value of approximately A$6 billion. In 2021, Infrastructure Victoria provided its advice to the Victorian Government on potential scenarios for repurposing Victoria’s gas transmission and distribution networks in a future where Victoria’s carbon emission reduction targets are achieved. This paper provides the results of assessment on the suitability of existing gas infrastructure across the value chain to be repurposed for hydrogen blending, 100% hydrogen, biomethane and carbon dioxide service. This work was performed for the purpose of informing the Victorian Government of the opportunities and risks to gas infrastructure associated with achieving its 2050 net zero emission target. more...

Presentation presented at theWesterdijk Spring Symposium Fungal Evolution held in Amsterdam on 17–18 April 2023

The benefits of scientific collaboration are too often skewed towards wealthier countries. Bioethicists and others present guidance on how stakeholders such as researchers can change this.

Keynote at the DGfM centernary meeting with Kick-Off meeting of Mycobiomics

This contribution seeks to answer the following question: To what extent does the Advertising Regulatory Board (ARB), as a public watchdog in the advertising industry, have the jurisdiction to consider advertising complaints filed against a person or entity which is not a member of the ARB? In Advertising Regulatory Board NPC v Bliss Brands (Pty) Ltd 2022 JDR 0769 (SCA), the Supreme Court of Appeal confirmed its earlier order in Advertising Standards Authority v Herbex (Pty) Ltd 2017 6 SA 354 (SCA) that the ARB possesses the jurisdiction to consider an advertising complaint irrespective of whether or not the relevant advertiser is a member of the ARB. Although non-member advertisers may elect not to subject themselves to the jurisdiction of the ARB or comply with an ARB ruling, all ARB rulings are issued for the adherence by the ARB's members. In the instance of a non-member who exercises its constitutional right to dissociate from the ARB and its adjudication process, the ARB may nevertheless consider an advertising complaint if there is a potential contravention of the ARB's Code of Advertising Practice. The SCA's ruling should be considered in the context of the important role that the ARB performs as a service to the general public. While the court a quo in the Bliss-matter attempted to derail this public function, the SCA has come to the aid of the general public in justifying the jurisdiction and public function of the ARB as a body which sets out and rules on ethically acceptable and responsible advertising for the benefit of consumers. Given the advantages of the ARB mechanism as it currently stands, it is submitted that the broader public interest may very well prevail should leave to appeal to the Constitutional Court be granted. more...

BACKGROUND: Access to primary health care is a fundamental right for all. However, persons with disabilities are experiencing difficulties when accessing healthcare because of various environmental and personal barriers which may lead to nonuse of such services OBJECTIVES: This study aimed to identify the challenges leading to non-use of healthcare services among persons with mobility impairments in Cofimvaba METHOD: A descriptive qualitative design using snowball sampling was implemented. Semistructured interviews were conducted in isiXhosa with five participants who stopped accessing healthcare, using a self-developed interview guide. Inductive thematic analysis was used to develop codes and themes from the data RESULTS: Study findings revealed major challenges experienced by persons with mobility impairments in accessing healthcare. These included inaccessible roads, geographic inaccessibility, financial accessibility and indirect cost of care, having little or not many health problems, physical infrastructure difficulties within facilities, and attitudinal barriers CONCLUSION: The findings indicated that persons with disabilities are experiencing a combination of structural and environmental challenges which make them stop accessing healthcare CONTRIBUTION: The article shares insights on access challenges that influence non-use of the often-needed healthcare services within the context of rural areas more...

Credit risk scorecards are logistic regression models, fitted to large and complex data sets, employed by the financial industry to model the probability of default of potential customers. In order to ensure that a scorecard remains a representative model of the population, one tests the hypothesis of population stability; specifying that the distribution of customers’ attributes remains constant over time. Simulating realistic data sets for this purpose is nontrivial, as these data sets are multivariate and contain intricate dependencies. The simulation of these data sets are of practical interest for both practitioners and for researchers; practitioners may wish to consider the effect that a specified change in the properties of the data has on the scorecard and its usefulness from a business perspective, while researchers may wish to test a newly developed technique in credit scoring. We propose a simulation technique based on the specification of bad ratios, this is explained below. Practitioners can generally not be expected to provide realistic parameter values for a scorecard; these models are simply too complex and contain too many parameters to make such a specification viable. However, practitioners can often confidently specify the bad ratio associated with two different levels of a specific attribute. That is, practitioners are often comfortable with making statements such as “on average a new customer is 1.5 times as likely to default as an existing customer with similar attributes”. We propose a method which can be used to obtain parameter values for a scorecard based on specified bad ratios. The proposed technique is demonstrated using a realistic example, and we show that the simulated data sets adhere closely to the specified bad ratios. The paper provides a link to a Github project with the R code used to generate the results. more...

BACKGROUND: Type 2 diabetes has been recognised as a global health concern: one that requires intervention to lessen the incumbrance caused by the chronic illness. This rapid review was conducted to determine the scientific evidence available on how Cognitive Behaviour Therapy (CBT) interventions improved the self-management of individuals with type 2 diabetes. AIM: The aim of the review was to synthesise current scientific evidence regarding CBT-based interventions and self-management practices. METHOD: The rapid review served as a framework to appraise current national and international literature. The researchers used Google Scholar, Journal Storage (JSTOR), PsycINFO, APA PsycArticles, SAGE journals and EBSCO Discovery Services to search for relevant studies. This was performed by employing keywords. Nine relevant studies were identified. The studies were heterogenous in methodology. Seven of the nine studies were conducted in developing countries RESULTS: The study found that the context of developmental countries plays a significant role in the development of type 2 diabetes and requires tailored intervention because of socio-economic variabilities. The main themes identified in relation to improving self-management included: the characteristics of the CBT-based interventions, namely the format, duration, and outcomes, and identifying the techniques and components used in the CBT-based interventions CONCLUSION: The review emphasised the need to further investigate the role of CBT in improving self-management of type 2 diabetes, especially in a South African context CONTRIBUTION: The review summarised the techniques that have proven to be effective for the self-management of type 2 diabetes more...

The Poisson distribution has a large number of applications and is often used as a model in both a practical and a theoretical setting. As a result, various goodness-of-fit tests have been developed for this distribution. In this paper, we compare the finite sample power performance of ten of these tests against a wide range of alternative distributions for various sample sizes. The alternatives considered include, seemingly for the first time, weighted Poisson distributions. A number of additional tests are of historical importance although their power performance is not competitive against the remaining tests. These tests are discussed, but their powers are not included in the numerical analysis. The Monte Carlo study presented below indicates that the test with the best overall power performance is the test of Meintanis and Nikitin (2008), followed closely by the test of Rayner and Best (1990) (originally studied in Fisher, 1950) more...

Background. Complications of respiratory infections including pleural effusion (PE) are associated with a high morbidity. Differentiating between PE caused by Mycobacterium tuberculosis (Mtb) infection and other bacterial infections in endemic areas is difficult in children, thus, impacting treatment. Objective. To investigate the aetiology of PE and features distinguishing tuberculosis (TB) from bacterial PE in children. Methods. We conducted a prospective study in children with PE admitted to a tertiary hospital in Cape Town from December 2017 to December 2019. Clinical information and routine laboratory investigations were compared between children with bacterial, Mtb or unclassified PE, categorised according to study definitions. Results. A total of 91 patients were included in the present study and their median age was 31 months (interquartile range (IQR) 11.8 - 102.1). The aetiology was bacterial in 40% (n=37), Mtb in 39% (n=36) and unclassified in 20% (n=18) of patients. Staphylococcus aureus was the most common bacterial isolate, confirmed in 65% (n=24/37) patients, and Streptococcus pneumoniae was confirmed in only 8% of patients. TB was microbiologically confirmed in 33% (n=12/36) of patients. Patients with TB were older (91.6 v. 11.8 months; p more...

Social housing has the potential to contribute to economic inclusion and urban integration if it is well-located. However, this is complicated by economic forces that shape land and property markets and constrain the ability of social housing organisations to afford suitable sites for development on the open market. The paper shows how South Africa’s transformative vision for social housing has been diluted by the gradual spatial drift of projects from the accessible urban core towards outlying areas. Poor coordination has meant that social housing organisations have operated in relative isolation without the consistent government support required to obtain surplus public land in well-situated areas. more...