SUNScholar
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Communities in DSpace
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Recent Submissions
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Minor Histories of the Pacific [Special Section]
(2012-05) Mishra, Sudesh; Smith, Russell
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Fact-Checking Role Performances and Problematic Covid-19 Vaccine Content in Latin America and Sub-Saharan Africa
(Cogitatio Press, 2024-10-14) Riedlinger, Michelle; Montana‐Nino, Silvia; Watt, Ned; Garcia‐Perdomo, Victor; Joubert, Marina
The move from political fact-checking to a “public health” or debunking model of fact-checking, sustained by policies and funding from platforms, highlights important tensions in the case of Covid-19. Building on findings from studies focused on journalistic role performance, we investigated how professional fact-checkers in Latin America and sub-Saharan Africa conceived of and performed their professional roles when addressing Covid-19 vaccination topics. Interviews with fact-checkers from six well-established, Meta-affiliated, International Fact-Checking Network-accredited organizations operating in these regions indicated that fact-checkers recognized the diversification of tasks and new roles associated with addressing problematic content from social media users. However, fact-checkers expressed unanimous commitment to prioritizing political and media watchdog activities in response to problematic Covid-19 vaccine information spreading from elite sources. To compare these role conceptions with role performance, we conducted a content analysis of Covid-19 vaccine content posted in 2021 to these fact-checkers’ Facebook accounts. We found that content was mostly associated with explainers or debunking content (addressing hoaxes or rumors about Covid-19 vaccines from non-elite social media users). In particular, the abundance of explainers, compared with other genres of fact-checking content, aligns fact-checkers with professional roles as civic service providers, educators, and “interpreters” of health information. Only a small proportion of the Covid-19 vaccine-related posts from each fact-checker contained verifications of claims from authoritative (elite “top-down”) sources (i.e., politicians, media, and health/science professionals). This study offers insights into a particularly tumultuous time of political activity in these regions and considers implications for practice innovation.
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Disentangling the relationships among abundance, invasiveness and invasibility in trait space
(Springer Nature, 2023-06-09) Hui, Cang; Pysek, Petr; Richardson, David M.
Identifying conditions and traits that allow an introduced species to grow and spread, from being initially rare to becoming abundant (defined as invasiveness), is the crux of invasion ecology. Invasiveness and abundance are related but not the same, and we need to differentiate these concepts. Predicting both species abundance and invasiveness and their relationship in an invaded community is highly contextual, being contingent on the community trait profile and its invasibility. We operationalised a three-pronged invasion framework that considers traits, environmental context, and propagule pressure. Specifically, we measure the invasiveness of an alien species by combining three components (performance reflecting environmental suitability, product of species richness and the covariance between interaction strength and species abundance, and community-level interaction pressure); the expected population growth rate of alien species simply reflects the total effect of propagule pressure and the product of their population size and invasiveness. The invasibility of a community reflects the size of opportunity niches (the integral of positive invasiveness in the trait space) under the given abiotic conditions of the environment. Both species abundance and the surface of invasiveness over the trait space can be dynamic and variable. Whether an introduced species with functional traits similar to those of an abundant species in the community exhibits high or low invasiveness depends largely on the kernel functions of performance and interaction strength with respect to traits and environmental conditions. Knowledge of the covariance between interaction strength and species abundance and these kernel functions, thus, holds the key to accurate prediction of invasion dynamics.
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An Evaluation of High‑Risk HPV in Squamous Cell Carcinomas of the Lip in a South African Cohort
(Springer Nature, 2024-05-06) Harbor, Sharon N.; Schneider, Johann W.; Solomons, Nadine; Sanderson, Micheline; Afrogheh, Amir H.
Background
To determine the prevalence of HR-HPV in a series of lip SCC from South African patients, using currently accepted HPV-testing methodologies and to define the clinical and histomorphologic features of HPV-associated lip SCC.
Methods
Fifty SCC of lip and 50 control cases were tested for HR-HPV using p16 and HR-HPV DNA PCR. p16-equivocal/positive and HPV DNA PCR-positive SCC were further evaluated for the expression of HPV-16 and HPV-18 mRNA transcripts using reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) to confirm transcriptionally active HPV.
Results
p16 was positive in 22% (n = 11) and equivocal in 4% (n = 2) of the SCC. One p16-positive case showed positivity for both HPV-16 DNA and HPV-16 E6/E7 mRNA transcripts (HPV prevalence rate of 2%). The HPV-positive case was non-keratinizing and occurred in an 80-year-old female. The two p16-equivocal cases were HR-HPV DNA positive and mRNA PCR negative. p16 was found to have a positive predictive value of 9%.
Conclusion
Findings from our cohort of lip SCC suggest that HR-HPV may have an insignificant role in the pathogenesis of SCC at this site. Due to its low ppv, p16 is insufficient to establish HR-HPV infection in SCC of the lip. The combination of p16 and DNA PCR appears to correlate with the presence of transcriptionally active virus. HPV E6/E7 mRNA detection is the gold standard for identifying HR-HPV. mRNA testing is not widely available in sub-Saharan Africa due to technical and financial constraints; however, the test appears to be of great value in p16-equivocal lip SCC.
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Rehabilitation and primary care treatment guidelines, South Africa
(World Health Organization, 2022-08-22) Conradie, Thandi; Charumbira, Maria; Bezuidenhout, Maryke; Leong, Trudy; Louw, Quinette
The World Health Organization recognizes rehabilitation as an essential component of universal health coverage (UHC). In many countries, UHC builds on a standard benefits package of services that is informed by the country’s essential medicines list, standard treatment guidelines and primary health care essential laboratory list. In South Africa, primary health care is largely provided and managed by primary health-care nurses and medical officers in accordance with primary health care standard treatment guidelines. However, rehabilitation is mostly excluded from these guidelines. This paper describes the 10-year process that led to rehabilitation referral recommendations being considered for inclusion in South Africa’s primary health care standard treatment guidelines. There were five key events: (i) a breakthrough moment; (ii) producing a scientific evidence synthesis and formulating recommendations; (iii) presenting recommendations to the national essential medicines list committee; (iv) mapping rehabilitation recommendations onto relevant treatment guideline sections; and (v) submitting revised recommendations to the committee for final consideration. The main lesson learnt is that, by working together, rehabilitation professionals can be of sufficient number to make a difference, improve service delivery and increase referrals to rehabilitation from primary health care. A remaining challenge is the lack of a rehabilitation representative on the national essential medicines list committee, which could hamper understanding of rehabilitation and of the complexities of the supporting evidence.