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Psychological transformation of the ‘self’ towards eco-sensitivity through high-risk nature-based sports : a South African context
(Routledge, 2024) Human, Nicolette; Steyn, Barend Johannes Marthinus
Mindless actions in the form of environmentally degrading behaviour constantly threaten the sustainability of healthy ecosystems. In this paper, the intrinsic value of strengthening the bond between humanity and nature through high-risk nature-based sports participation is explored. This interpretative phenomenological analytical study considers lived experiences of 10 skilled South African high-risk nature-based sports participants who take calculated risks through precautionary measures. Participant’s activities are performed in the wilderness in isolation from civilisation with minimal availability of human and medical resources in case of an emergency, which give rise to the term ‘high-risk.’ Phenomenological traditions from Heidegger and Merleau-Ponty navigate a hermeneutical understanding of theirbodily-being-towards-death. Evidence of meaningful psychological transformation towards an eco-sensitivity by way of high-risk nature-based sports participation is analysed, through first-hand narratives via semi-structured interviews. The sensitizing process of the ‘self’ can be effectively articulated in the synchronous relationship between the Eigenwelt, Mitwelt and Umwelt.
Size, scaling, and sexual size dimorphism in wild South African thick-tailed greater galagos (Otolemur crassicaudatus)
(Springer, 2024-12) Leigh, Steven R.; Sauther, Michelle L.; Cuozzo, Frank P.; Tordiffe, Adrian Stephen Wolferstan; Van Wyk, Ilana
The developmental bases of sexual size dimorphism vary across primates, with important implications for understanding the evolution of dimorphism. Here, we explore adult sexual size dimorphism and its developmental bases in Otolemur crassicaudatus. We aim to understand the anatomical pattern of adult sexual size dimorphisms and their developmental bases through allometric analyses of somatometrics. We caught and released wild subadult and adult animals annually at Lajuma Research Centre, South Africa from 2013 to 2023 (excepting 2020), and measured body mass and up to 23 body measurements. Among adults, males (mean body mass = 1242.89 g ± SD = 137.63 g, n = 91 observations of n = 52 individuals) are 1.21 times larger than females (mean body mass = 1027.55 g ± SD = 94.03 g, n = 85 observations of n = 44 individuals), possibly representing the highest body mass sexual dimorphism among extant strepsirrhines. The skeletal system shows limited sexual size dimorphism, suggesting decoupling of body mass size dimorphism and skeletal size dimorphism. Allometries lead to variation in adult sexual size dimorphism throughout the body, with high levels of dimorphism in circumferences, especially in the torso and proximal limb elements. Sexual selection, attributable to some level of intermale competition, probably accounts for sexual size dimorphism in this species. The conservatism of the skeletal system, combined with high body mass size dimorphism, may be related to generalized quadrupedalism and declining rates of leaping through ontogeny in the species. These findings complicate reconstructing and interpreting primate sexual size dimorphism in the fossil record.
Triage of HPV positivity in a high HIV prevalence setting : a prospective cohort study comparing visual triage methods and HPV genotype restriction in Botswana
(Wiley, 2024-05) Luckett, Rebecca; Ramogola-Masire, Doreen; Gompers, Annika; Moraka, Natasha; Moyo, Sikhulile; Sedabadi, Leatile; Tawe, Leabaneng; Kashamba, Thanolo; Gaborone, Kelebogile; Mathoma, Anikie; Noubary, Farzad; Kula, Maduke; Grover, Surbhi; Dreyer, Greta; Botha, Matthys H.; Makhema, Joseph; Shapiro, Roger; Hacker, Michele R.
OBJECTIVE : Guidelines for effective triage following positive primary high-risk human papillomavirus (HPV) screening in low- and middle-income countries with high human immunodeficiency virus (HIV)-prevalence have not previously been established. In the present study, we evaluated the performance of three triage methods for positive HPV results in women living with HIV (WLHIV) and without HIV in Botswana.
METHODS : We conducted baseline enrollment of a prospective cohort study from February 2021 to August 2022 in South-East District, Botswana. Non-pregnant women aged 25 or older with an intact cervix and no prior diagnosis of cervical cancer were systematically consented for enrollment, with enrichment of the cohort for WLHIV. Those who consented completed a questionnaire and then collected vaginal self-samples for HPV testing. Primary HPV testing for 15 individual genotypes was conducted using Atila AmpFire® HPV assay. Those with positive HPV results returned for a triage visit where all underwent visual inspection with acetic acid (VIA), colposcopy, and biopsy. Triage strategies with VIA, colposcopy and 8-type HPV genotype restriction (16/18/31/33/35/45/52/58), separately and in combination, were compared using histopathology as the gold standard in diagnosing cervical intraepithelial neoplasia (CIN) 2 or worse (CIN2+).
RESULTS : Among 2969 women enrolled, 1480 (50%) tested HPV positive. The cohort included 1478 (50%) WLHIV; 99% were virologically suppressed after a mean of 8 years on antiretroviral therapy. In total, 1269 (86%) women had histopathology data for analysis. Among WLHIV who tested positive for HPV, 131 (19%) of 688 had CIN2+ compared with 71 (12%) of 581 in women without HIV. Screening by 8-type HPV genotype restriction was more sensitive as triage to detect CIN2+ in WLHIV 87.79% (95% CI: 80.92–92.85) and women without HIV 85.92% (95% CI: 75.62–93.03) when compared with VIA (WLHIV 62.31% [95% CI: 53.39–70.65], women without HIV 44.29% [95% CI: 32.41–56.66]) and colposcopy (WLHIV 70.77% [95% CI: 62.15–78.41], women without HIV 45.71% [95% CI: 33.74–58.06]). However, 8-type HPV genotype restriction had low specificity in WLHIV of 30.88% (95% CI: 27.06–34.90) and women without HIV 37.06% (95% CI: 32.85–41.41). These results were similar when CIN3+ was used as the outcome. When combining 8-type HPV genotype restriction with VIA as the triage strategy, there was improved specificity to detect CIN2+ in WLHIV of 81.65% (95% CI: 78.18–84.79) but dramatically reduced sensitivity of 56.15% (95% CI: 47.18–64.84).
CONCLUSIONS : Eight-type HPV genotype restriction is a promising component of effective triage for HPV positivity. However, novel triage strategies in LMICs with high HIV prevalence may be needed to avoid the trade-off between sensitivity and specificity with currently available options.
CLINICAL TRIALS REGISTRATION : This study is registered on Clinicaltrials.gov no. NCT04242823, https://clinicaltrials.gov/ct2/show/NCT04242823.
Empirical modeling and meta-analysis of heat transfer in plate heat exchangers
(Taylor and Francis, 2024) Mukkamala, Yagnavalkya; Dirker, Jaco
Plate heat exchangers provide a compact and efficient alternative to bulky and spacious shell-and-tube heat exchangers. With numerous plates and flow passages, plate heat exchangers increase the flow transit time and enhance hot-fluid-to-cold fluid contact promoting higher heat transfer rates than conventional designs. Plate condensers and evaporators offer cost-effective, compact, and highly efficient alternatives to traditional surface condensers and evaporators. This article reports the empirical modeling and meta-analysis of over two-thousand heat transfer data compiled from thirty-five experimental investigations in the past three decades. The predictive correlations validated against an extensive database should be helpful to the industry and academia. Meta-analysis of the phase-change heat transfer data was statistically insignificant, and the current practice of deploying plate heat exchangers should be encouraged.
Solitary fibrous tumor of the mandible
(Springer, 2024-12) Fonseca, Thamyres Campos; Agostini, Michelle; Paes, Jefferson Viapiana; Roza, Ana Luiza Oliveira Correa; Van Heerden, Willem Francois Petrus; Romanach, Mario Jose; Abrahao, Aline Correa
A 41-year-old woman presented with a facial asymmetry in the mental region and a painful, well-circumscribed, tender mass in the right lower buccal vestibule, associated with extensive ill-defined bone rarefaction with subtle cortical bone resorption. Microscopically, a proliferation of bland spindle cells interspersed with collagen fibers and prominent staghorn-like blood vessels was observed. Immunohistochemical analysis revealed strong positivity for CD34, Bcl-2, CD99, and STAT-6, confirming the diagnosis of Solitary Fibrous Tumor (SFT). Conservative surgical enucleation was performed, and 4 years later, recurrence was observed with extensive bone involvement and moth-eaten margins resembling a malignant tumor. SFT is a distinctive spindle cell tumor of fibroblastic differentiation, characterized by prominent branching staghorn-like vessels and a specific NAB2::STAT6 gene fusion. We herein contribute with a central SFT of the mandible with recurrent behavior and radiographic appearance suggesting malignancy.