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Prioritising African perspectives in psychiatric genomics research

- Kamaara, Eunice, Kong, Camillia, Campbell, Megan M

Authors: Kamaara, Eunice , Kong, Camillia , Campbell, Megan M
Date: 2020
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/302520 , vital:58204 , xlink:href="https://doi.org/10.1111/dewb.12248"
Description: Psychiatric genomics research with African populations comes with a range of practical challenges around translation of psychiatric genomics research concepts, procedures, and nosology. These challenges raise deep ethical issues particularly around legitimacy of informed consent, a core foundation of research ethics. Through aconsideration of the constitutive function of language, the paper problematises like‐for‐like, designative translations which often involve the ‘indigenization’ of English terms or use of metaphors which misrepresent the risks and benefits of research. This paper argues that effective translation of psychiatric genomics research terminology in African contexts demands substantive engagement with African conceptual schemas and values. In developing attenuated forms of translational thinking, researchers may recognise the deeper motivational reasons behind participation in research, highlighting the possibility that such reasons may depart from the original meaning implied within informed consent forms. These translational issues might be ameliorated with a critical re-examination of how researchers develop and present protocols to institutional ethics review boards.
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Privacy risk and the use of Facebook Apps: a gender-focused vulnerability assessment

- Van der Schyff, Karl, Flowerday, Stephen, Furnell, Steven

Authors: Van der Schyff, Karl , Flowerday, Stephen , Furnell, Steven
Date: 2020
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/149054 , vital:38800 , https://doi.org/10.1016/j.cose.2020.101866
Description: The surveillance and subsequent privacy risks (i.e., misuse of personal information) of Facebook App data constitute a persistent problem that affects millions of users. However, despite Facebook App research on specifics such as privacy concerns, value of information, and demographics, none of them has conducted vulnerability assessments on the use of Facebook Apps as influenced by specific factors such as age, gender, and information privacy attitudes. As such, the purpose of this study was to predict the extent to which these factors influence an individual's intention to continue using Facebook Apps as part of a gender-focused vulnerability assessment. We evaluate two hypotheses by way of ordinal logistic regression using data gathered from 621 respondents. The results are indicative of the following: First, females are particularly vulnerable to privacy risks as a function of continued use of Facebook Apps. More specifically, those risks related to Facebook's access to personal information. Second, results indicate that a user's age is nonsignificant in relation to the continued use of Facebook Apps. We conclude with several theoretical and practice-oriented information privacy recommendations.
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Probing the structural dynamics of the Plasmodium falciparum tunneling-fold enzyme 6-pyruvoyl tetrahydropterin synthase to reveal allosteric drug targeting sites:

- Khairallah, Afrah, Ross, Caroline J, Tastan Bishop, Özlem

Authors: Khairallah, Afrah , Ross, Caroline J , Tastan Bishop, Özlem
Date: 2020
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/163057 , vital:41008 , https://doi.org/10.3389/fmolb.2020.575196
Description: The de novo folate synthesis pathway is a well-established drug target in the treatment of many infectious diseases. Antimalarial antifolate drugs have proven to be effective against malaria, however, rapid drug resistance has emerged on the two primary targeted enzymes: dihydrofolate reductase and dihydroptoreate synthase. The need to identify alternative antifolate drugs and novel metabolic targets is of imminent importance. The 6-pyruvol tetrahydropterin synthase (PTPS) enzyme belongs to the tunneling fold protein superfamily which is characterized by a distinct central tunnel/cavity. The enzyme catalyzes the second reaction step of the parasite’s de novo folate synthesis pathway and is responsible for the conversion of 7,8-dihydroneopterin to 6-pyruvoyl-tetrahydropterin. In this study, we examine the structural dynamics of Plasmodium falciparum PTPS using the anisotropic network model, to elucidate the collective motions that drive the function of the enzyme and identify potential sites for allosteric modulation of its binding properties.
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Prospects for the biological control of Iris pseudacorus L(Iridaceae)

- Minuti, Gianmarco, Coetzee, Julie A, Ngxande-Koza, Samella W, Hill, Martin P, Stiers, Iris

Authors: Minuti, Gianmarco , Coetzee, Julie A , Ngxande-Koza, Samella W , Hill, Martin P , Stiers, Iris
Date: 2020
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/417776 , vital:71485 , xlink:href="https://doi.org/10.1080/09583157.2020.1853050"
Description: Native to Europe, North Africa and western Asia, Iris pseudacorus L. (Iridaceae) has invaded natural and human-modified wetlands worldwide. This species is considered a noxious weed in several countries including Argentina, South Africa and New Zealand. Its broad ecological tolerance, high resilience and reproductive potential make current mechanical and chemical control measures cost-ineffective, and biological control is considered a suitable alternative. In order to prioritise candidate biocontrol agents, a list of organisms reported to attack the plant within its native range has been assembled, and information about their host-range and damaging potential gathered from the literature. Furthermore, surveys for natural enemies of the plant were conducted in Belgium and northern Italy. The insect fauna associated with I. pseudacorus at the sites surveyed comprised mostly incidental visitors and polyphagous feeders, with the exception of the sawfly Rhadinoceraea micans Klug (Hymenoptera: Tenthredinidae), the seed weevil Mononychus punctumalbum Herbst (Coleoptera: Curculionidae), and the flea beetle Aphthona nonstriata Goeze (Coleoptera: Chrysomelidae). The potential of these species for biocontrol was evaluated, and A. nonstriata was given highest priority. A population of this species was imported to quarantine in South Africa, where it is currently undergoing host-specificity testing. Importation of the two remaining candidates is expected shortly. In conclusion, the prospects for the biological control of I. pseudacorus appear promising.
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Protected and un-protected urban wetlands have similar aquatic macroinvertebrate communities: a case study from the Cape Flats Sand Fynbos region of southern Africa

- Blanckenberg, Michelle, Mlambo, Musa C, Parker, Denham, Motitsoe, Samuel N

Authors: Blanckenberg, Michelle , Mlambo, Musa C , Parker, Denham , Motitsoe, Samuel N
Date: 2020
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/149288 , vital:38822 , https://0-doi.org.wam.seals.ac.za/10.1371/journal.pone.0233889
Description: Rapid urbanisation has led to major landscape alterations, affecting aquatic ecosystems’ hydrological and biogeochemical cycles, and biodiversity. Thus, habitat alteration is considered a major driver of aquatic biodiversity loss and related aquatic ecosystem goods and services. This study aimed to investigate and compare aquatic macroinvertebrate richness, diversity and community structure between urban temporary wetlands, located within protected and un-protected areas. The latter were found within an open public space or park with no protection or conservation status, whereas the former were inaccessible to the public and had formal protected, conservation status.
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Quality by Design Optimization of Cold Sonochemical Synthesis of Zidovudine-Lamivudine Nanosuspensions:

- Witika, Bwalya A, Smith, Vincent J, Walker, Roderick B

Authors: Witika, Bwalya A , Smith, Vincent J , Walker, Roderick B
Date: 2020
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/148424 , vital:38738 , https://doi.org/10.3390/pharmaceutics12040367
Description: Lamivudine (3TC) and zidovudine (AZT) are antiviral agents used to manage HIV/AIDS infection. The compounds require frequent dosing, exhibit unpredictable bioavailability and a side effect profile that includes hepato- and haema-toxicity. A novel pseudo one-solvent bottom-up approach and Design of Experiments using sodium dodecyl sulphate (SDS) and α-tocopheryl polyethylene glycol succinate 1000 (TPGS 1000) to electrosterically stablize the nano co-crystals was used to develop, produce and optimize 3TC and AZT nano co-crystals. Equimolar solutions of 3TC in surfactant dissolved in de-ionised water and AZT in methanol were rapidly injected into a vessel and sonicated at 4 °C.
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Quantifying ecosystem restoration recovery and restoration practice following the biological control of invasive alien macrophytes in Southern Africa

- Motitsoe, Samuel Nkopane

Authors: Motitsoe, Samuel Nkopane
Date: 2020
Subjects: Salvinia molesta , Ceratophyllum demersum , Nymphaea mexicana , Invasive plants -- Biological control -- South Africa , Aquatic weeds -- Biological control -- South Africa , Restoration monitoring (Ecology) -- South Africa , Biolotical invasions -- Environmental aspects
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/167519 , vital:41488
Description: Invasive alien aquatic plants (IAAP) species are known to have deleterious effects on the freshwater ecosystems they invade. This includes both socio-economic and ecologically important ecosystem goods and services. Thus, IAAP species are declared a serious threat, second only to habitat modification for causing a loss of aquatic biodiversity. Three control methods have been widely applied to control IAAP species invasion globally; mechanical, chemical and biological control. Both mechanical and chemical control methods are considered short-term and expensive, whereas biological control methods are regarded an effective and long-term solution for IAAP species control at the landscape level. But, little is known of the ecological recovery following the biological control of IAAP species, with mechanical control known to have had mixed success and chemical control to have non-targeted effects on aquatic ecosystems, causing harm to wildlife and human well-being. Biological control practitioners measure the success of biological control based on: (1) the biological control agents’ establishment and the negative impacts they impose on the targeted weed; and (2) the weeds biomass reduction and an increase in native macrophytes species. Arguably, measures of biological control success have been subjective and variable across the globe. Although some field studies have demonstrated biological control success to have positive socio-economic returns, there is little literature on ecological benefits. Furthermore, there is limited understanding on ecosystem recovery and possible restoration efforts following the biological control IAAP species, as compared to alien weeds in terrestrial and riparian ecosystems. Thus, this thesis aimed to quantify the ecological recovery i.e. aquatic biodiversity, ecosystem processes and trophic interactions following the management of Salvinia molesta in freshwater ecosystems. The research employed a suite of Before-After Control-Impact mesocosm and field studies to investigate the response of aquatic microalgae, macroinvertebrates and their interactions (food web structure and function) during S. molesta infestation and after mechanical and biological control. The mesocosm experiment (Before invasion, During invasion & After control) showed that both aquatic microalgae and macroinvertebrate diversity indices were reliable biological indicators of S. molesta ecological impacts and recovery following control. The restored treatment (100% S. molesta cover + biological control agents), demonstrated complete aquatic microalgae and macroinvertebrate recovery following biological control, similar to the control treatment (open water), where the degraded/impacted treatment (100% S. molesta cover with no biological control agents) showed a drastic decline in aquatic biodiversity and a complete shift in aquatic biota assemblage structure. Thus, the biological control effort by Cyrtobagous salviniae, the biological control agent for S. molesta, assisted in the recovery of aquatic biota following successful biological control. The field study (four field sites, two sites controlled mechanically and two biologically) investigated water quality, aquatic biodiversity and community trophic interactions (aquatic food web) “before and after” S. molesta control. The study showed a drastic decline in aquatic biodiversity (with three sites showing no record of aquatic macroinvertebrates, thus no biotic interactions during infestation) and poor water quality due to the shade-effect (light barrier due to floating S. molesta mats on the water surface) during the “before” S. molesta control phase. However, following both mechanical and biological control (“after” S. molesta control phase), there was a significant shift in abiotic and biotic ecosystem characteristics as compared to the “before” S. molesta control phase. Thus, rapid ecosystem recovery was apparent as a result of aquatic microalgae and macroinvertebrates recolonisation. Sites showed a normal functioning ecosystem where improved water quality, increased biodiversity, productivity and trophic interactions, was indicative of the return of biologically and functionally important species which were lost during the “before” S. molesta phase. Although the clear water state showed positive outcomes at Westlake River, these were short lived when the system was dominated by a cosmopolitan submerged Ceratophyllum demersum, and later replaced by a floating-leaved emergent IAAP Nymphaea mexicana. Each state was responsible for a significant shift in both biotic and abiotic characteristics, affirming macrophyte abilities to influence aquatic environments structure and functions. Furthermore, this event showed a clear example of a secondary invasion. Thus, a holistic IAAP species management strategy is necessary to restore previously invaded ecosystems and prevent subsequent secondary invasion and ecosystem degradation. In conclusion, the S. molesta shade-effect like any other free-floating IAAP species, was identified as the main degrading factor and responsible for water quality reduction, loss of aquatic diversity and shift in aquatic biota assemblage structure. Following S. molesta removal (or shade-effect elimination), there was a positive response to aquatic ecosystem species abundance, richness, diversity and community structure. Therefore, in combination, aquatic biota recolonisation rate and increases in biological and functional diversity were instrumental in the recovery of ecosystem structure and functions, following the control of S. molesta. Echoing existing literature, this thesis recommends: (1) IAAP species management programmes (mechanical and/or biological control) should not only aim to control the weed but also focus on ecosystems recovery and possible restoration goals; (2) biological control should be used where appropriate to combat free-floating IAAP species in freshwater ecosystems, followed by active introduction of native macrophyte propagules since they are limited by anthropogenic activities; and (3) more freshwater case studies are needed to add to our understanding of IAAP species management and restoration effort incorporating long-term monitoring.
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Quantifying the impacts of abrasion and bacterial transfer when fish are exposed to sand during a catch-and-release event:

- Foster, Ryan M, Childs, Amber-Robyn, Brooks, Margot, Farthing, Matthew W, Butler, Edward C, Potts, Warren M

Authors: Foster, Ryan M , Childs, Amber-Robyn , Brooks, Margot , Farthing, Matthew W , Butler, Edward C , Potts, Warren M
Date: 2020
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/160427 , vital:40445 , https://doi.org/10.2989/1814232X.2020.1792982
Description: Best-practice guidelines to improve recreational fishers’ handling during catch-and-release (CandR) events are critical to improve the conservation and management of fish stocks worldwide. While best-practice research is growing, there are knowledge gaps, with the effects of sand exposure on fish mucous membranes understudied. This study aimed to determine the effects of exposing a fish to sand during a CandR event. A total of 360 juvenile (48–137 mm TL) Cape stumpnose Rhabdosargus holubi were subjected to a simulated CandR event during which they were either held: (i) with wet hands, or (ii) dry hands; or with wet hands and then placed on either (iii) wet sterilised sand, (iv) dry sterilised sand, (v) wet unsterilised sand, or (vi) dry unsterilised sand. Fish were maintained in a recirculating system for two weeks, euthanised and subjected to an examination of their mucous layer (bacterial counts, abrasion counts and percentage of abrasion area) and an internal biological assessment. Bacteria fro m fish mucous layers were cultivated on agar plates to count bacterial colonies.
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Radio and X-ray detections of GX 339–4 in quiescence using MeerKAT and Swift:

- Tremou, E, Corbel, S, Fender, R P, Woudt, P A, Miller-Jones, J C A, Motta, S E, Heywood, I, Armstrong, R P, Groot, P, Horesh, A, Van der Horst, A J, Koerding, E, Mooley, K P, Rowlinson, A, Wijers, R A M

Authors: Tremou, E , Corbel, S , Fender, R P , Woudt, P A , Miller-Jones, J C A , Motta, S E , Heywood, I , Armstrong, R P , Groot, P , Horesh, A , Van der Horst, A J , Koerding, E , Mooley, K P , Rowlinson, A , Wijers, R A M
Date: 2020
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/149862 , vital:38907 , https://0-doi.org.wam.seals.ac.za/10.1093/mnrasl/slaa019
Description: The radio–X-ray correlation that characterizes accreting black holes at all mass scales – from stellar mass black holes in binary systems to supermassive black holes powering active galactic nuclei – is one of the most important pieces of observational evidence supporting the existence of a connection between the accretion process and the generation of collimated outflows – or jets – in accreting systems. Although recent studies suggest that the correlation extends down to low luminosities, only a handful of stellar mass black holes have been clearly detected, and in general only upper limits (especially at radio wavelengths) can be obtained during quiescence. We recently obtained detections of the black hole X-ray binary (XRB) GX 339–4 in quiescence using the Meer Karoo Array Telescope (MeerKAT) radio telescope and Swift X-ray Telescope instrument on board the Neil Gehrels Swift Observatory, probing the lower end of the radio–X-ray correlation. We present the properties of accretion and of the connected generation of jets in the poorly studied low-accretion rate regime for this canonical black hole XRB system.
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Rational design and regioselective synthesis of conformationally restricted furan-derived ligands as potential anti-malarial agents

- Mutorwa, Marius K, Nokalipa, Iviwe, Tanner, Delia C, Blatch, Gregory L, Lobb, Kevin A, Klein, Rosalyn, Kaye, Perry T

Authors: Mutorwa, Marius K , Nokalipa, Iviwe , Tanner, Delia C , Blatch, Gregory L , Lobb, Kevin A , Klein, Rosalyn , Kaye, Perry T
Date: 2020
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/447170 , vital:74589 , xlink:href="https://doi.org/10.24820/ark.5550190.p011.281"
Description: Substituted 3-furanomethyl phosphate esters and their corresponding phosphoric acids have been prepared as conformationally restricted analogues of DOXP, the natural substrate for Plasmodium falciparum 1-deoxyD-xylulose-5-phosphate reductoisomerase (PfDXR), and fosmidomycin, an established inhibitor. Saturation Transfer Difference (STD) NMR analysis and in silico docking data suggest the potential of such compounds as PfDXR inhibitors.
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Re-adjustment of masculinities and sexualities amongst first year male students at Rhodes University in the wake of the residence Consent Talk’s programme

- Ntisana, Thulani

Authors: Ntisana, Thulani
Date: 2020
Subjects: Communication in higher education - South Africa -- Makhanda , Rape in universities and colleges -- South Africa -- Makhanda , Masculinity -- South Africa -- Makhanda , Male college students -- Social life and customs -- South Africa -- Makhanda , Male college students -- Sexual behavior -- South Africa -- Makhanda , Male college students -- Conduct of life -- South Africa -- Makhanda , Men -- Identity , Male domination (Social structure) , Patriarchy -- South Africa , Women -- Violence against -- South Africa , Social problems -- South Africa , Consent Talks , #RUreferencelist
Language: English
Type: text , Thesis , Masters , MA
Identifier: http://hdl.handle.net/10962/148956 , vital:38790
Description: This study seeks to understand how Rhodes University first-year male students adjusted and re-adjusted their masculinities and sexualities in light of the Consent Talk programme offered by the university, the aim of which is to liberate masculinities and femininities from patriarchal and dominant discourses. In the past 26 years, South Africa has seen an increase in academic research establishing causal links between boys, men, masculinities and a number of social ills such as the HIV/AIDs epidemic, violence against women, substance abuse, homophobia, gender-based violence and a lower pass rate amongst boys. This in turn inspired an increase in interventions seeking to involve boys and men in order to identify and address their role in combating gender based violence. These various forms of social deviances that have been linked to masculinity have indicated that young men's masculinity is in crisis and as a result needs great attention in order to address the social issues linked to them. Institutions of higher learning have proven to be microcosms of the larger society. Universities have become highly sexualised spaces; coercive sexual practices in heterosexual relationships are a norm, young women don't feel safe and have lost confidence in universities addressing their concerns. With the emergence of the #RUreferencelist in 2016, the spotlight fell on Rhodes University; young women challenged the rape culture and sexual assaults on campus. In 2016, staff members who are well-informed and educated on issues of gender, sexuality and rape initiated discussions with students in their residences; these discussions were later to be called the Consent Talks. This research makes use of Pierre Bourdieu’s critical theory in understanding how young men negotiate their masculinity within the field of higher education, at Rhodes University. Bourdieu’s three main concepts, field, habitus and capital are used to describe how young men negotiate their masculinity and how the field of gender intersects with the field of higher education. A qualitative paradigm has been employed. The study has collected data through the use of in-depth interviews to get a richer insight into the participants’ perspectives. There were 15 interviews conducted in total for this study, 14 were with first year male students, and one with a senior official of the University. The data was analysed through a qualitative thematic analysis. The findings of the research reveal that some of the participants were exposed to patriarchal and dominant forms of masculinity when growing up. However, most of the participants revealed they were also exposed to alternative masculinities. These were either taught or learnt at home, from family members, circumcision school, church or peers in society. Both the dominant and alternative masculinities were revealed in the discourses of what it means to be a man and in how the young men performed their masculinities. Furthermore, one of the major themes that emerged was that most of the young men in the study were raised by single mothers with mothers playing a significant role in encouraging healthy masculinities. The findings went on to reveal that families (mothers, fathers, older siblings and culture) play a role in socialising and shaping healthy masculinities. The acceptance or rejection of either dominant or alternative masculinities was influenced by an exposure to an environment that either encouraged or shunned either dominant or alternative masculinities. The findings further unveils that different societies are strongly identified with their own definitions of what it means to be a man and are not open to other definitions of masculinity. Moreover, most of the participants accepted the content of what was taught in the Consent Talks; however sought healthy participation, interaction and inclusion of female students. Lastly, the study has also revealed that knowledge of the consequences of breaking (the law) university’s policy does affect some change of behaviour in potential perpetrators.
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Reconstructing the distribution of the non-native sea anemone, Diadumene lineata (Actiniaria), in the Canadian Maritimes: local extinction in New Brunswick and no regional range expansion in Nova Scotia since its initial detection

- Ma, Kevin C K, Glon, Heather E, Hawk, Heather L, Chapman, Cody N

Authors: Ma, Kevin C K , Glon, Heather E , Hawk, Heather L , Chapman, Cody N
Date: 2020
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/179054 , vital:40095 , https://doi.org/10.1016/j.rsma.2020.101049
Description: Since its first observations in New Brunswick (Sam Orr’s Pond) and Nova Scotia (Bedford Institute of Oceanography in Dartmouth) in 2009 and 2013, respectively, Diadumene lineata has been observed spreading to new locations in the Canadian Maritimes. In 2017 and 2018, regional surveys for non-native species did not detect D. lineata in New Brunswick, suggesting local extinction. Recent surveys also did not detect D. lineata in Prince Edward Island. However, between 2013 and 2018, D. lineata was detected in Nova Scotia (in chronological order) from Lunenburg Harbour (Lunenburg), Hermans Island (Lunenburg), Black Rock Beach (Halifax), Oak Island Marina (Chester), and Dartmouth Yacht Club (Dartmouth).
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Reef fish associations with benthic habitats at a remote protected coral reef ecosystem in the Western Indian Ocean-Aldabra Atoll, Seychelles

- Haupt, Philip

Authors: Haupt, Philip
Date: 2020
Subjects: Coral reef ecology -- Aldabra Islands (Seychelles) , Reef fishes -- Aldabra Islands (Seychelles) , Benthic animals -- Aldabra Islands (Seychelles)
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/141629 , vital:37991
Description: The aim of the thesis is to develop an understanding of the associations between reef fish and benthic habitats and assess the modifying effects of environmental processes on these relationships at Aldabra, a pristine atoll in the Western Indian Ocean (WIO). Conducting research in pristine, or reference coral reef ecosystem, removes the impact of direct anthropogenic disturbances and provides essential information on natural ecosystem structure and functioning. Three primary hypotheses were tested: 1) Environmental drivers such as depth and exposure to wave energy determine the spatial distribution of benthic habitats; 2) The reef fish assemblage structure is explained by habitat at multiple scales and modified by the effects of environmental drivers such as depth, wave energy and cyclical temporal drivers such as time and tides; 3) The reef fish assemblage at Aldabra represents a pristine reef fish assemblage, comprising high levels of herbivores and predators. The research focussed on the benthic habitat on the seaward reefs between the shoreline and 50 m depth. The first objective was to characterise the benthic habitats on Aldabra Atoll’s seaward reefs and map their spatial distributions using remotely sensed imagery and ground truthing data. The second was to assess the influence of depth and exposure to wave energy on the distribution of benthic habitats. The third was to identify the most suitable standardised method to survey the reef fish assemblage structure on Aldabra’s, and fourth to determine the effect of tide and time of day on the reef fish assemblage. The fifth objective was to establish the association between reef fish assemblage structure and benthic habitats and to test how species-size influenced the scale of habitat at which the associations were most apparent. Four categories of geomorphic reef zones (reef flats (19.2 km2), top of the forereef slope (7.8 km2), deep forereef slope (11.6 km2), and reef platform (14.3 km2)) were manually delineated following the visual outlines of reef features from satellite imagery. The six broad-scale and twelve fine-scale benthic habitats were mapped using a supervised maximum likelihood classification and the spatial coverage of each determined. The broad-scale habitats were 1) Epilithic algal matrix, 2) Hard and soft (coral, 3) Rubble, 4) Macroalgae, 5) Seagrass and 6) Sand. Similarly, twelve fine-scale benthic habitats were characterised and mapped, for example, Hard coral (19 %) including massive and submassive forms with Millepora and Rhytisma. The broad-scale benthic habitat map had an overall producer accuracy of 54 % and fine-scale habitat map 29 %, which was consistent with studies using similar habitat classification methods. The prevailing wave energy, depth and the directional orientation of coral reefs (aspect) significantly influenced the probability of occurrence of each of the broad-scale benthic habitats, and there was a shift in peak probability of occurrence of all habitat categories to a greater depth with an increase in wave energy. The strong relationship of benthic habitats with depth and wave energy suggests that the distributions of benthic habitats are likely to change with sea-level rise and increased intensity and frequency of storms in future. Overall, 338 fish species from 51 families, including 14 species of elasmobranch were recorded using Baited Remote Underwater Video systems (BRUVs) and unbaited Remote Underwater Video systems (RUVS) from 231 samples. Fish were significantly more abundant when observed using BRUVs (119 ± 7) relative to RUVs (92 ± 7), and the assemblage structures were significantly different between the two sampling methods. Abundance and species richness of generalist carnivores and piscivores were significantly greater in BRUVs, while RUVs recorded significantly greater numbers of herbivores and more species of herbivore and corallivore. The results suggest that BRUVs are better suited when studying predatory fish which may not be detected without bait. However, when surveying a taxonomically and functionally diverse assemblage of fishes at a pristine reef, RUVs may provide a more accurate estimate of natural reef fish assemblage structure. Reef fish assemblages observed using RUVs were significantly different between morning-high-tide, midday-low-tide and evening-high-tide for all trophic groups. However, the reef fish assemblage structure observed using BRUVs was insensitive to change in tide and time of day, which may be explained by the attraction effect of bait dampening the effect of tide and time of day. While RUVs appear better to detect more subtle variations in fish assemblage structure, care needs to be taken when designing research programmes that use RUVs, as the sampling design should account for tide and time of day to avoid misinterpreting the cyclical variation, which may confound results. Reef fish assemblages were significantly different among habitats within geomorphic reef zones, broad-scale and fine-scale habitats. Species turnover rates were significantly different for all Actinopterygii size-class categories between the three scales of habitat. No marked differences in species turnover rates among habitats were detected for the majority of Elasmobranch size-class categories. The strong habitat dependency over various spatial scales indicates that effective conservation of Actinopterygii fish at Aldabra, and elsewhere in similar ecosystems requires protection of representative sets of benthic habitats. However, Elasmobranch conservation requires sufficiently large areas as these species utilise multiple habitats, over multiple scales, which are likely to exceed the confines of Aldabra’s reef.
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Regularly drinking desert birds have greater evaporative cooling capacity and higher heat tolerance limits than non‐drinking species

- Czenze, Zenon J, Kemp, Ryno, van Jaarsveld, Barry, Freeman, Marc T, Smit, Ben, Wolf, Blair O, McKechnie, Andrew

Authors: Czenze, Zenon J , Kemp, Ryno , van Jaarsveld, Barry , Freeman, Marc T , Smit, Ben , Wolf, Blair O , McKechnie, Andrew
Date: 2020
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/441585 , vital:73900 , https://doi.org/10.1111/1365-2435.13573
Description: Surface water is a critical resource for many birds inhabiting arid re-gions, but the implications of regular drinking and dependence on sur-face water for the evolution of thermal physiology remain largely unex-plored. We hypothesized that avian thermoregulation in the heat has evolved in tandem with the use of surface water and predicted that (a) regularly drinking species have a greater capacity to elevate rates of evaporative water loss (EWL) compared to non‐drinking species, and (b) heat tolerance limits (HTLs) are higher among drinking species. To test these predictions, we quantified thermoregulatory responses to high air temperature (Ta) in 12 species of passerines from the South African arid zone and combined these with values for an additional five species. We categorized each species as either: (a) water‐dependent, regularly drinking, or (b) water‐independent, occasional‐/non‐drinking.
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Regulation of Kaposi’s Sarcoma-Associated Herpesvirus Biology by Host Molecular Chaperones:

- Kirigin, Elisa, Ruck, Duncan Kyle, Jackson, Zoe, Murphy, James, McDonnell, Euan, Okpara, Michael O, Whitehouse, Adrian, Edkins, Adrienne L

Authors: Kirigin, Elisa , Ruck, Duncan Kyle , Jackson, Zoe , Murphy, James , McDonnell, Euan , Okpara, Michael O , Whitehouse, Adrian , Edkins, Adrienne L
Date: 2020
Language: English
Type: text , book
Identifier: http://hdl.handle.net/10962/165385 , vital:41239 , ISBN , https://0-doi.org.wam.seals.ac.za/10.1007/7515_2020_18
Description: Kaposi’s sarcoma-associated herpesvirus (KSHV) is a gammaherpesvirus associated with development of the human diseases Kaposi’s sarcoma, Primary Effusion Lymphoma and Multicentric Castleman’s Disease. KSHV establishes a chronic latent infection in hosts, with periods of viral lytic replication, where both latent and lytic virus cycles contribute to malignancy, most often in the immunodeficient host.
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Reimagining academic identities in response to research demands at Universities of Technology

- Gumbi, Thobani, McKenna, Sioux

Authors: Gumbi, Thobani , McKenna, Sioux
Date: 2020
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/185897 , vital:44446 , xlink:href="https://doi.org/10.14426/cristal.v8i1.234"
Description: In the last volume of this journal, Garraway and Winberg called for a reimagination of Universities of Technology (UoT) within the South African higher education system. This article continues that conversation by looking at the implications that the formation of the UoT had for academics’ identities. Technikon lecturers’ identities were closely tied to workplace expertise, but demands for research in UoTs have changed this. A social realist analysis of interviews with fifteen academics at three UoTs finds that research remains a contested issue. Interviewees understood research to take the form of acquiring postgraduate qualifications, rather than as an ongoing activity tied to their identities. Echoing Garraway and Winberg’s study, the bureaucratic nature of the institutional culture was referred to as a constraint. There was also a view that for this programme, Dental Technology, a demand for research was needed from industry if this was to be a valued aspect of academics’ identities.
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Rejection of the genetic implications of the “Abundant Centre Hypothesis” in marine mussels

- Ntuli, Noxolo N, Nicastro, Katy R, Zardi, Gerardo I, Assis, Jorge, McQuaid, Christopher D, Teske, Peter R

Authors: Ntuli, Noxolo N , Nicastro, Katy R , Zardi, Gerardo I , Assis, Jorge , McQuaid, Christopher D , Teske, Peter R
Date: 2020
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/444839 , vital:74302 , https://www.nature.com/articles/s41598-020-57474-0
Description: The ‘Abundant-Centre Hypothesis’ is a well-established but controversial hypothesis stating that the abundance of a species is highest at the centre of its range and decreases towards the edges, where conditions are unfavourable. As genetic diversity depends on population size, edge populations are expected to show lower intra-population genetic diversity than core populations, while showing high inter-population genetic divergence. Here, the genetic implications of the Abundant-Centre Hypothesis were tested on two coastal mussels from South Africa that disperse by means of planktonic larvae, the native Perna perna and the invasive Mytilus galloprovincialis. Genetic structure was found within P. perna, which, together with evidence from Lagrangian particle simulations, points to significant reductions in gene flow between sites. Despite this, the expected diversity pattern between centre and edge populations was not found for either species. We conclude that the genetic predictions of the Abundant-Centre Hypothesis are unlikely to be met by high-dispersal species with large population sizes, and may only become evident in species with much lower levels of connectivity.
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Relational hubs for collaborative landscape stewardship

- Cockburn, Jessica J, Cundill, Georgina, Shackleton, Sheona E, Cele, Ayanda, Cornelius, Susanna F, Koopman, Vaughan, Le Roux, Jean-Pierre, McLeod, Nicky, Rouget, Mathieu, Schroder, Samantha, Van den Broek, Dieter, Wright, Dale R, Zwinkelse, Marijn

Authors: Cockburn, Jessica J , Cundill, Georgina , Shackleton, Sheona E , Cele, Ayanda , Cornelius, Susanna F , Koopman, Vaughan , Le Roux, Jean-Pierre , McLeod, Nicky , Rouget, Mathieu , Schroder, Samantha , Van den Broek, Dieter , Wright, Dale R , Zwinkelse, Marijn
Date: 2020
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/392748 , vital:68789 , xlink:href="https://doi.org/10.1080/08941920.2019.1658141"
Description: Landscape stewardship is considered an important place-based approach to addressing sustainability challenges. Working at landscape-level requires collaboration between diverse landscape stakeholders. In this study, we partnered with local stewardship practitioners across six cases in South Africa to investigate how they facilitate collaboration towards social-ecological sustainability outcomes. We found that practitioners facilitate collaboration among stakeholders by operating as relational hubs in the landscape. Through these hubs, they build new inter-personal relationships among stakeholders, creating social networks which enable stewardship practice. The hubs deepen human-nature relationships by creating enabling conditions for stewards to put stewardship ethics into action. Drawing on insights from these cases, we call for a relational approach to landscape stewardship which focuses on human-to-human and human-to-nature relationships. Moreover, we argue that landscape stewardship initiatives need to re-focus stewardship on stewards, recognizing them as key agents of change in addressing the conflict between agriculture and conservation inherent in many landscapes.
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