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Personality traits and emotional intelligence as predictors of sustainable commercial agricultural producers in South Africa

  • Authors: Posthumus, Karen-Louise
  • Date: 2016
  • Subjects: Sustainable agriculture -- South Africa Emotional intelligence -- South Africa Agriculture -- Economic aspects -- South Africa
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10948/10399 , vital:26742
  • Description: The dual agriculture sector in South Africa comprises both a well-developed commercial farming and a smaller scale communal component. It is however, the commercial sector that is relied upon for food security. The multi-dimensional and complex nature of agricultural production in South Africa demands that sustainable commercial farmers of the future need to demonstrate the ability to effectively handle a multitude of tasks, which may be a function of individual personality traits and emotional intelligence. In this paper, the contribution of individual differences in personality and emotional intelligence as drivers for sustainability of South African commercial agricultural producers was investigated for inclusion into a selection model defining the entry-level requirements (skills, knowledge and competencies) for this occupation. Despite several studies that reported on the personality traits of farmers on a global level, no reports are found on similar studies conducted within a South African context. The main objective of this study was to improve the sustainability of all commercial agricultural producers in South Africa by investigating the personality traits and emotional intelligence driving that sustainability. This study focused on the commercial farming sector in South Africa, which has a unique need to integrate emerging/new farmers into the modern agricultural value chain. This is in accordance with the objectives of the Land Reform Bill (South Africa, 2015) as set out in the government’s National Development Plan (South Africa, 2012). The population of the study comprised commercial agricultural producers throughout South Africa and the sample frame was the estimated 40 000 commercial agricultural producers from whom the sample was drawn. The sampling method employed was snowball sampling (non-probability sampling) with the sampling unit selected on a degree of personal judgement. Quantitative questionnaires were administered to 60 commercial farmers throughout South Africa. Quantitative data was analysed using the STATISTICA Version 10.0 (2011) computer software programme and results were presented in tabulated format. The empirical results revealed that amongst the independent variables investigated in this study, only two variables were significantly related to the successful implementation of sustainable farming; they are neuroticism and management of emotions. Emanating from the findings of this study, recommendations were made to respective role-players on how to manage and support these findings.
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  • Date Issued: 2016

Personality traits and self-presentation on Facebook: a systematic review

  • Authors: Venter, Doreen Yvonne
  • Date: 2016
  • Subjects: Facebook (Electronic resource) -- Psychological aspects Personality Social media -- South Africa -- Psychological aspects
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/13272 , vital:27170
  • Description: The influence of the Internet and Computer Mediated Communication (CMC) on the ways in which individuals with different personality traits present themselves, has been brought into question increasingly as modern life requires more and more of an enmeshment with technology in everyday life. The presentation of the self on Facebook has been the focus of recent research, delivering results that vary and sometimes contradict common ideas of the effects of individuals’ interaction via technology, especially in terms of how personality traits, as determined by the Five-factor model, impact self-presentation. A systematic review of the available literature was conducted, in order to bring about a consolidated description of the literature on the impact of personality traits on Facebook self-presentation. From 37 studies, the review found the motivation for Facebook use to be a mediating factor in the relationship between personality traits. Each personality trait in the Five-factor model impacts upon Facebook use, self-generated content, other-generated content, and the nature of the individual’s self-disclosure in varied ways. Due to visible cues on users’ profiles, some personality traits can be accurately detected by observers. The complexity and interrelatedness of variables involved in this relationship is highlighted by the findings of this review.
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  • Date Issued: 2016

Perspectives of Post Graduate Certificate in Education (PGCE) students on the effectiveness of school based mentoring

  • Authors: Baartman, Nomakhaya
  • Date: 2016
  • Subjects: Mentoring in education -- South Africa -- Eastern Cape Teachers -- In-service training -- South Africa -- Eastern Cape Student teachers -- Supervision of -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: http://hdl.handle.net/10353/5641 , vital:29354
  • Description: Effective mentoring is essential for the development of student-teachers. A sequential explanatory mixed method study was conducted in order to analyse the perspectives of Post Graduate Certificate of Education (PGCE) students on the effectiveness of school based mentoring. Thirty-six (36) PGCE students from a higher education institution in the Eastern Cape participated in this study. Firstly, quantitative questionnaires were used to gather data from all the participants followed by qualitative semi–structured interviews from a purposive sample of five (5) participants in order to enrich the study. This study analysed PGCE students’ perspectives of mentor teacher practices. In doing so the study evoked Hudson and Peards’ Five Factor Mentoring Model. This model includes Personal Attributes, Systems Requirements, Pedagogical Knowledge, Modelling and Feedback. From the findings, PGCE students reported that Teaching Practice (TP) is a stressful period full of anxieties, excitement and fears, hence they need to be guided and supported by knowledgeable and specialist teachers (mentors). Mentors play a significant role in supporting and guiding student-teachers during TP. From the analysis of PGCE students’ perspectives, the research suggested that those who were supported and guided by their mentors experienced positive mentoring during TP. Those who experienced negative mentoring reported limited time for mentoring and unavailability of the mentors as the causes. They further expressed that they wished mentors were understanding, good models who treated them as teacher candidates not as students and gave them constructive feedback. Finally, they indicated that the partnership between host schools and the university needs to be improved.
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  • Date Issued: 2016

Perspectives of the historical–biographical criticism In the creative works of J. J. R. Jolobe

  • Authors: Khumalo, Hlonpha Pamela Vivienne , Kwatsha, Linda Loretta
  • Date: 2016
  • Subjects: South African literature -- History and criticism -- Biography Xhosa literature -- History and criticism
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10948/21983 , vital:29809
  • Description: Olu phando lohlalutyo lukwaluncomo-gxeko lwemisebenzi kaJolobe, injongo yalo kukubonisa ukuba lukho uqhagamshelwano phakathi kobomi bakhe jikelele kunye noncwadi lwakhe. Ulwazi olunjalo lungathi lube luncedo kwiphulo elibalulekileyo ekuncediseni kulwazi lokubhala ibhayografi yakhe. Kubonakele kufanelekile ukuba iphulo elinjalo lenziwe ukukhumbula imisebenzi emikhulu eyenziwe ngamaqhawe abantu abaNtsundu abathe banegalelo elikhulu ekuphakanyiswni koncwadi lwemvelo kwakunye nenkuqubela phambili kwimfundo yabantu abangama-Afrika beli lizwe. Umzekelo uJolobe ulusebenzele ukuba uncwadi lwakhe ukuxwayisa abantu bakowabo abaNtsundu ngemfundo nolwazi olwakhaya. Ukwalusebenzise uncwadi lwakhe ukuvusa abantu ama-Afrika balumke kwingozi zemimoya yocinezelo lwabo ngurhulumente ocalule abantu abaNtsundu kuba bebantsundu ngebala. Nangona uncwadi lwakhe ulenze lwabasisonwabiso kodwa ikhakhulu ulusebenzise kwanokunika intuthuzelo, ithemba kwanokomelela kubantu abathe bacinezelwe zimeko zobomi ukuba bangalahli ithemba loluzuza impumelelo, kuba izinto zingatshintsha ebomini babo ngokuhamba kwamaxesha. Kwakhona ukongeza uncwadi lwakhe ulusebenzise ukuphakamisa nokuhambisela phambili ulwimi lwemveli, inkcubeko, imbali ngokusebenzisa isixhobo esiluncwadi lwakhe ukuze ezi ngongoma zikhankanyisweyo zihlale ezincwadini zakhe ezithe zazisele zolwazi, zingabi nakuze zife kuba zililifa lesizwe esiNtsundu, Uninzi loncwadi olubhalwe nguJolobe luthe lwaxoxwa kwesi sifundo, kodwa kuye kwaphonongwa ikakhulu uncwadi lwemibongo, inoveli idrama kuba kubonakele ukuba lo msebenzi ubanzi kakhulu kwaye esi sifundo kubonakele ukuba kungabanzima ukuba singagqibeka lula, kodwa ke uJolobe ubengumntu okhutheleyo. Ubhale incwadi eziliqela ngenxa yothando lwakhe lobhalo loncwadi oluqhutywe ngumbono wakhe wobuthandazwe, wokubona kubalulekile ukuba inani loncwadi olubhaliweyo esiXhoseni linyuke kwaye libe kwizinga eliphezulu, ukuze umzi wasemaXhoseni nowamanye ama-Afrika ngokubanzi ungalambathi ngoncwadi lokufunda ujongelwe phantsi ngokuba semva kwinkqubela phambili zezinye izizwe Ingokuphandle uncwadi lukaJolobe lubonakela luyinxenye yobomi bakhe. Kulunye uncwadi kwakhe kufumaniseka ukuba ukubhale endululwe zizinto ezithe azamphatha kakuhle ebomini bakhe zazaza ezo zinto zawuphazamisa umoya wakhe, nentlalo yakhe wada waqanda ukuba makabhale aphokoze okukuphuphuma kwengcinga zakhe ukuzithuthuzela kwanokuphilisa kwanabanye abantu abathe badibana neenzima ezinjalo zobomi. Umzekelo: iimeko zopolitiko zeli lizwe zithe zabuchaphazela ubomi bakhe, oko kubesisiphumo sokuba abhale incwadi yakhe yedrama apho adiza ngeemeko zokuphatheka kwabantu baseBhayi kwilokishi eyathi yabelwa bona ngurhulumnte wobandlululo, apho ebexelenga khona njengetitshala kwanoMfundisi weliZwi. Kanti noncwadi apho athe wabonisa ukuvuya khona olo luvuyo olusukela kwinto ethe yamvuyisa emalunga nobomi bakhe, izimvo zakhe kwanenkolo yakhe njengomntu, kwanendlela akhule ngayo. Umzekelo, uJolobe uye wazisa abafundi bakhe ukuba iimbalo zakhe zisukele kwizinto ezithe zamchukumisa ebomini bakhe. Ngoko ke kwabonakala ukuba olu phando luluncedo ekusungulweni kweprojekti yokubhalwa kwebhayografi kaJolobe neya kuba luncedo kwimisebenzi yophando olubalulekileyo kuncwadi kuba iincwadi ezinje zityebile ngolwazi olubalulekileyo ekungena kucingelwa ukuba lunokufunyanwa kulo.
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  • Date Issued: 2016

Petrogenetic implications for the Merensky Reef: a platinum-group element distribution study from wide-reef facies in the western Bushveld Complex, RSA

  • Authors: Largatzis, Savvas Anthony
  • Date: 2016
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/3167 , vital:20380
  • Description: Despite decades of research and its economic importance, the formation of the Merensky Reef still remains controversial. This study reports on the distribution of platinum-group elements within widereef facies in an attempt to identify petrogenetic controls in the formation of the Merensky Reef. Widereef Merensky was sampled from Eland Platinum Mines in the western Bushveld. Macroscopic investigation of the drillcore identified a basal chromitite stringer overlying an anorthositic footwall. The reef comprised a pyroxenite unit while the hangingwall comprised noritic, leuconoritic and anorthositic units (upwards the stratigraphy). Furthermore, an anorthositic seam was identified within the pyroxenite reef, near the top of the unit. Ophitic textures of orthopyroxene oikocrysts comprising inclusions of plagioclase chadacrysts suggest that the crystallization of plagioclase preceded the crystallization of orthopyroxene. Furthermore, plagioclase and orthopyroxene were shown to be in mineral disequilibrium with one another. Pervasive hydrous alteration features throughout the Merensky Reef suggest late stage deuteric alteration. Mineral chemistry of plagioclase cores recorded ranges for An content in the Merensky Reef as follows: An72-79 in the anorthositic footwall, An71-77 in the chromitite stringer, An45-78 in the pyroxenite reef unit, An47-73 in the anorthosite reef unit, An72-76 in the norite hangingwall, An75-77 in the leuconorite hangingwall and An72-77 in the anorthosite hangingwall. This suggest that the reef units were more evolved than the footwall and hangingwall units. Furthermore, plagioclase showed reverse zoning in the anorthosite footwall unit while normal zoning was identified in the anorthosite reef unit. This suggested that the footwall unit underwent reheating and re-equilibration with a hotter, more primitive magma (also evident in recrystallization textures) while the anorthositic reef unit cooled relatively slowly and interstitial plagioclase present within this unit equilibrated with a trapped, more evolved liquid. The pyroxenite reef unit shows enrichment in incompatible elements and corresponding negative Eu anomalies, indicating the presence of trapped liquids. Cu, Ni and S concentrations remained low throughout the reef with the exception of a peak underlying the anorthositic seam and further enrichment underlying this peak. Platinum-group element geochemistry identified two major peaks: an upper peak which coincided with the peaks for Cu, Ni and S, and showed preferential enrichment in Pd and Au relative to other PGE, and a lower peak which coincided with the presence of chromitite and showed the preferential enrichment of Os, Ir, Ru, Rh and Pt relative to Pd, Au, Cu and Ni. The formation of the lower peak was consistent with a model involving the co-precipitation of chromite and PGE clusters (as PGM) while the upper peak was attributed to a model involving the collection of PGE by an immiscible sulphide liquid. Moreover, high Cu/Pd and Pt/Pd ratios in the lower pyroxenite unit indicated a process involving sulphide fractional segregation and scavenging while the inverse, present within the upper pyroxenite unit, suggested a more dynamic system involving the introduction of PGE-undepleted magma and S during simultaneous sulphide precipitation. Furthermore, a separation of PPGE peaks from IPGE peaks was observed within the pyroxenite unit, indicating a different partitioning behavior between PPGE and IPGE. The separation of these peaks is attributed to a sulphide liquid fractionation model while depletion haloes occurring in the proximity of the main PGE peaks was suggested to form through an Ostwald-ripening type mechanism. The results of this study are consistent with a model for the formation of the Merensky Reef involving a combination of geochemical processes, including sulphide segregation and fractionation, as well as multiple replenishments of magma.
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  • Date Issued: 2016

Pharmacological studies of Foeniculum Vulgare (Mill.) and Lippia Javanica (Burm.F.) spreng. used as spices in Nkonkobe Municipality of the Eastern Cape Province, South Africa

  • Authors: Asowata-Ayodele, Abiola Mojisola
  • Date: 2016
  • Subjects: Medicinal plants -- South Africa -- Eastern Cape Fennel -- Utilization -- South Africa -- Eastern Cape Ethnopharmacology -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10353/2777 , vital:28085
  • Description: Spices are of great importance in the indigenous culinary and traditional medicine systems of the people of Nkonkobe Municipality of the Eastern Cape, South Africa. The present investigation evaluated the ethnopharmacological potentials of two indigenous South African spices- Foeniculum vulgare and Lippia javanica. The pharmacological investigations on these two plant species include ultra-morphology, nutrient and mineral analysis, evaluation of the essential oil, phytochemical and antioxidant assays, antimicrobial, anti-inflammatory as well as anti-urolithiatic assay of the acetone and aqueous extracts of the two plants. The species were selected for study as the most cited plants after an ethnobotanical survey conducted on the indigenous knowledge of plants used as spices and medicine in Nkonkobe Municipality, Eastern Cape of South Africa. Among the plants cited Foeniculum vulgare(Apiaceae) and Lippia javanica (Verbenaceae) stood out as the most commonly used spices. Others were members of the families; Solanaceae, Apiaceae, Amaryllidaceae, Amaranthaceae and Lamiaceae. Ultra-morphological studies conducted on the leaves of the two selected plants using scanning electron microscope revealed the presence of non-glandular and glandular trichomes, stomata and crystals. The leaf surfaces of these herbs may serve as secretory sites where aromatic secondary metabolites are produced. Analyses of the proximate, mineral, vitamin and anti-nutrients contents of these two spices showed that both species are good sources of these phytochemicals and may be used to enrich the human diet. Lippia javanica possesses lower lipid (0.50 percent), fibre (5 percent) and carbohydrate (64.96 percent) contents than Foeniculum vulgare. On the other hand, protein (20.54 percent), ash (11.60 percent) and moisture content (11.69 percent) were higher in Foeniculum vulgare than in Lippia javanica. Foeniculum vulgare showed higher N (3286 mg/100g), Mg (386.7 mg/100g), K (3187 mg/100g) and Na (1383 mg/100g) content while Lippia javanica was higher in Ca (1833 mg/100g), Zn (4.7 mg/100g), Cu (0.9 mg/100g) and Fe (78.4 mg/100g). Vitamins Aand E were also higher in Lippia javanica (1.31 mg/100g; 2.52 mg/100g) while Foeniculum vulgare (0.45 mg/100g) had higher vitamin C content. No significant differences were observed in the phytate, oxalate and tannin contents of the two spices, but saponin and cyanide were significantly lower in Lippia javanica (268.5 mg/100g; 8.45 mg/100g) than in Foeniculum vulgare (1855 mg/100g; 10.5 mg/100g) Evaluation of the essential oil component, cytotoxicity and antimicrobial activities of both fresh and dried leaves of Lippia javanica and Foeniculum vulgare revealed that the dried samples yielded more oil and also contain more chemical than the fresh samples of both plants. The overall antimicrobial activity evaluated using susceptibility and microdilution assays revealed that the oils of F. vulgare and L. javanica exhibited high antifungal and antibacterial activity, compared to the reference drugs. In addition, essential oil from fresh leaves of both spices was less toxic compared to the oil from the dried leaves. Polyphenolic evaluation of the aqueous and acetone extracts of the plants revealed that the acetone extract had higher phenol, flavanol, flavonoid and proanthocyanidin contents than the aqueous extracts. The total phenolic content of acetone and aqueous extracts were 4.49 ± 0.411 mg/g and 3.73 ± 0.498 mg/g tannic acid equivalent (TAE) respectively for Lippia javanica. The same trend was also observed in Foeniculum vulgare with total phenolic content of acetone and aqueous extracts were 4.22 ± 0.325 mg/g and 4.17 ± 0.651 mg/g tannic acid equivalent (TAE) respectively. Further assessment of the antioxidant activity of the solvent extracts revealed that both plants exhibited promising free radical scavenging potentials against 1,1 diphenyl-2-picrylhydrazyl (DPPH), 2, 2’-azino-bis(3- ethylbenzthiazoline-6-sulfonic acid (ABTS), reducing power, lipid peroxidation, nitric oxide, phosphomolybdate and hydrogen peroxide. Antimicrobial activities of the acetone and aqueous extracts of the two plants revealed moderate antibacterial and antifungal activities. They inhibited the growth of Microsporium canis and Trichophyton rubrum that were not susceptible to the standard antifungal drug used as control.
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  • Date Issued: 2016

Photographing other selves: collecting, collections and collaborative visual identity

  • Authors: Minkley, Hannah Smith
  • Date: 2016
  • Subjects: Documentary photography -- South Africa Semiotics -- South Africa
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: http://hdl.handle.net/10948/12669 , vital:27105
  • Description: This study is situated in a social documentary photography context, and is concerned to explore whether the collaborative interaction between photographer, subject (as collector) and material object (as collection) might enable a practice that presents a more mutual and subject-centred visual identity emerge. In particular, photographers Jim Goldberg and Gideon Mendel have focused more on the subject themselves, using collaborative processes such as photo-voice and photo elicitation, as well as the use of peoples’ handwritten captions on photographic prints themselves. Claudia Mitchell’s overview of visual methodologies is drawn on, together with Ken Plummer’s Documents of Life 2 (2001) and Gillian Rose’s Visual Methodologies (2001) to extend on these possibilities of conducting collaborative visual research.The practical component of this study focuses on personal collections and follows a number of theorists, including Susan Pearce, and John Elsner and Roger Cardinal. It follows Pearce’s identification of three major modes of collecting, and suggests that collections are essentially narratives of the self, and reveal experiences and expressions of personal desire. By drawing on these approaches and the various ways the twelve collectors were photographed, as well as implementing collaborative research processes (handwritten text, archival photographs and the re-staging of the collections), the study confirms Pearce’s three primary modes of collecting, and acknowledges that they are often interlinked or overlap one another. The study further found that a more subject voiced visual identity did indeed become apparent through the collaborative methods applied and discussed. The collaborative research equally demonstrated that these narratives of identity are not singular, but rather narratives of multiple, personal identities of the self.
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  • Date Issued: 2016

Photophysical properties of tetraphenylporphyrinsubphthalocyanine conjugates

  • Authors: Managa, Muthumuni , Mack, John , Remiro-Buenamañana, Sonia , Tshangana, Charmaine , Cammidge, Andrew N , Nyokong, Tebello
  • Date: 2016
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/240766 , vital:50869 , xlink:href="https://doi.org/10.1142/S1088424615500959"
  • Description: Novel tetraphenylporphyrin-subphthalocyanine conjugates have been prepared and characterized. An analysis of their optical spectroscopy and electronic structures using fluorescence emission and magnetic circular dichroism (MCD) spectroscopy and TD-DFT calculations, demonstrates that the two chromophores do not interact to any significant extent.
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  • Date Issued: 2016

Photophysicochemical properties of nanoconjugates of zinc (II) 2 (3)-mono-2-(4-oxy) phenoxy) acetic acid phthalocyanine with cysteamine capped silver and silver–gold nanoparticles

  • Authors: Oluwole, David O , Prinsloo, Earl , Nyokong, Tebello
  • Date: 2016
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/188552 , vital:44764 , xlink:href="https://doi.org/10.1016/j.poly.2016.09.034"
  • Description: A novel asymmetrical zinc(II) 2(3)-mono-2-(4-oxy)phenoxy)acetic acid phthalocyanine (complex 1) was synthesized and subsequently linked to cysteamine capped silver (AgNPs) and silver–gold (AgAuNPs) nanoparticles (NPs) via amide bonds. The photophysicochemical properties and in vitro photodynamic therapy activity of complex 1 and its nanoconjugates were investigated. The nanoconjugates showed improved photophysical properties compared to complex 1 alone. The fluorescence, triplet and singlet quantum yields of complex 1 were found to be 20%, 48%, and 43% respectively. Complex 1 showed in vitro dark cytotoxicity, but the dark toxicity was reduced for the combination of complex 1 with AgAuNPs, this combination also gave the best photodynamic therapy activity when compared to complex 1 and its conjugate with AgNPs without AuNPs.
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  • Date Issued: 2016

Phylogenetic radiation of the greenbottle flies (Diptera, Calliphoridae, Luciliinae).

  • Authors: Williams, Kristin A , Lamb, Jennifer , Villet, Martin H
  • Date: 2016
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/441431 , vital:73887 , 10.3897/zookeys.568.6696
  • Description: The subfamily Luciliinae is diverse and geographically widespread. Its four currently recognised genera (Dyscritomyia Grimshaw, 1901, Hemipyrellia Townsend, 1918, Hypopygiopsis Townsend 1916 and Lucilia Robineau-Desvoidy, 1830) contain species that range from saprophages to obligate parasites, but their pattern of phylogenetic diversification is unclear. The 28S rRNA, COI and Period genes of 14 species of Lucilia and Hemipyrellia were partially sequenced and analysed together with sequences of 11 further species from public databases. The molecular data confirmed molecular paraphyly in three species-pairs in Lucilia that hamper barcode identifications of those six species. Lucilia sericata and Lucilia cuprina were confirmed as mutual sister species. The placements of Dyscritomyia and Hypopygiopsis were ambiguous, since both made Lucilia paraphyletic in some analyses. Recognising Hemipyrellia as a genus consistently left Lucilia s.l. paraphyletic, and the occasionally-recognised (sub)genus Phaenicia was consistently paraphyletic, so these taxa should be synonymised with Lucilia to maintain monophyly.
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  • Date Issued: 2016

Phylogenetics and historical biogeography of the Teloganodidae (Ephemeroptera)

  • Authors: Pereira da Conceicoa, Lyndall Louise
  • Date: 2016
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/64900 , vital:28629
  • Description: The Teloganodidae are a mayfly family endemic to the southwestern Cape (South Africa), with relatives in Madagascar and Asia. Like many other aquatic invertebrates in Africa, they have been considerably understudied. Research into biodiversity and biogeography allows an understanding of the earth’s biota, producing knowledge which can be used to develop strategies to preserve and monitor this biota. Mismanagement of water systems places biodiversity of river fauna under an ever-increasing extinction threat. This investigation explores rivers in under-collected areas to determine how well teloganodids have been represented in the literature, with four genera and five species described at the onset of this study. A lectotype for Lestagella penicillata Barnard (1940) has been elected and described in detail, setting “benchmark” characters for future descriptions. Standard DNA sequencing methods provide portions of three mitochondrial genes; cytochrome oxidase subunit I (COI), small subunit ribosomal 16S RNA (16S), 12S ribosomal DNA (12S) and two nuclear genes, Histone 3 (H3) and 28S ribosomal DNA (28S) for up to 255 specimens. Fore and hind wings of 79 teloganodid adults were used to examine phylogenetic signal and evolutionary divergence using geometric morphometrics. A multi-faceted approach is used to investigate relationships between clades and the effects of deep-time climatic and landform changes which have influenced the diversity and distribution seen today. Tree (Bayesian Inference and Maximum Likelihood) and network (parsimony) phylogenies, ancestral reconstruction, historical biogeography and wingevolution of the Teloganodidae are investigated. Species tree analyses discovered 27 species and six genera. Distinct lineages are restricted to catchments, and strong phylogeographic structure was found within most genera. Southern African Teloganodidae are shown to have originated in the Cretaceous, with divergence and dispersal of lineages depended on their established locality at the time of tectonic events (uplift) and climatic changes (sea level regressions and transgressions). Geographic clines in wing-shape of Lestagella across its range imply evolutionary adaptations to specific catchment landscape and environment. A detailed analysis of biodiversity has many valuable contributions, from directing future research, understanding adaptive processes, fine-tuning phylogeographical and evolutionary hypotheses, to improving management and conservation decisions in order to preserve endemic biodiversity hotspots.
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  • Date Issued: 2016

Phylogenetics of the keratin-feeding beetle family Trogidae (Coleoptera: Scarabaeoidea)

  • Authors: Strümpher, Werner Petrus
  • Date: 2016
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/1232 , vital:20037
  • Description: Trogidae constitute a monophyletic and biologically unique family within the Scarabaeoidea, being the only keratinophagous group in its superfamily. Traditionally, the family has been divided into three distinctive genera, Omorgus Erichson, Polynoncus Burmeister, and Trox Fabricius. Although the taxonomy of the group is relatively well studied, recently changes to the existing classification have been proposed without the family as currently constituted being subjected to phylogenetic analyses. In this study I present the first molecular phylogeny for this cosmopolitan family, based on three partially sequenced gene regions: 16SrRNA, 18S rRNA and 28S rRNA domain 2. Analyses resolved relationships between and within genera and subgenera that are largely congruent with existing taxonomic hypotheses based on morphology. I recovered four well-supported radiations: Polynoncus, Omorgus, Holarctic Trox and Afrotropical Phoberus. One of the more surprising results was the monophyly of Phoberus. Based on the evidence, I propose reinstating the genus Phoberus to accommodate all Afrotropical (including Madagascan endemic) species. The results re-emphasise the validity of Scholtz’s (1986a) classification system for the genus Omorgusand its subgeneraand provide evidence of an African origin for Madagascan trogids. Divergence analysis was able to date the major events for the origin of extant lineages of Trogidae. The subsequent diversification of the major lineages is largely attributed to Pangaean and Gondwanan vicariance events in the Mid-Jurassic and early Late Cretaceous, respectively. The separation of the landmasses resulted in the evolution of four distinct groups: Omorgus, Polynoncus, Trox and Phoberus. The monophyletic subgenus Phoberus MacLeay is of particular interest; about one-third (14 of 40) of the species in the Afrotropical region have lost the ability to fly. To gain insights into the evolution of flightlessness in this clade, phylogenetic relationships among species were inferred using molecular sequence data. Four partial sequences of four genes (COI, 16S, 18S and 28S domain 2) were obtained for 27 species, covering all of the recognised species-groups. Estimated times of divergence were based on published mutation rates for COI. The results recovered eight monophyletic lineages, supporting the morphology-based subdivisions of the genus. Flightlessness evolved at least five times within the subgenus. There is no strong support for the re-acquisition of functional wings once they are lost. Diversification, and the present relictual distributions, in African Phoberus can be linked to climatic and geological events associated with the Miocene and Pliocene Climate Optimum in southern Africa. The evolution of flightlessness in Phoberus is consistent with the habitat stability hypothesis. All flightless species occupy refugial areas with relatively long-term environmental stability. Phoberus is a promising model group for studying evolutionary trends relating to flightlessness, speciation and biogeography. Flightlessness is a counterintuitive evolutionary development, given the many advantages of flight. To interpret the diversification in the flightless Phoberus capensis Scholtz, the phylogenetic relationships among several populations of P. capensis are investigated. Phylogenetic relationships among populations were inferred using molecular sequence data that suggested three distinct evolutionary lineages, which was also supported by morphological characters. Divergence time estimates suggest a Pliocene-Pleistocene diversification. Based on these results, it is suggested that P. capensis experienced climatically-driven allopatric speciation with sheltered Afrotemperate forests and high mountain peaks serving as important refugia in response to climatic exacerbations. The P. capensis complex thus represents a speciation process in which flight-restricted populations evolved in close allopatry, possibly as recently as the Pleistocene. Two of the three divergent and geographically distinct lineages are described as novel species. This study represents the most recent comprehensive work on the Trogidae. On the basis of this study, it is proposed that taxonomic changes to the generic classification of the family be made. Trogidae are formally divided into two subfamilies, Omorginae and Troginae. The subgenus Phoberus is restored to genus rank to include all the Afrotropical species, and Afromorgus is confirmed at subgeneric rank. The genus Madagatrox is synonymised with Phoberus.
  • Full Text:
  • Date Issued: 2016

Physical properties of solid-state erythromycin derived compounds

  • Authors: Neglur, Rekha R
  • Date: 2016
  • Subjects: Erythromycin -- Thermal properties , Azithromycin -- Thermal properties
  • Language: English
  • Type: Thesis , Doctoral , DPhil
  • Identifier: http://hdl.handle.net/10948/7228 , vital:21308
  • Description: This thesis investigated the physical properties of the macrolide antibiotics: Erythromycin dihydrate (EM-DH), Roxithromycin monohydrate (RM-MH) and Azithromycin dihydrate (AZM-DH). The abovementioned hydrate compounds were investigated in terms of the hydrate-anhydrate crystal structure stability, dehydration and observed polymorphism under controlled temperature heating programs. Identified hydrate and anhydrate polymorphs were subjected to physical stability testing during controlled storage. EM-DH was characterized by thermal analysis (DSC, TGA), X-ray diffraction, FTIR and microscopy. Dehydration of EM-DH at temperatures of 100, 157 and 200°C (followed by supercooling to 25°C) produced the form (I) anhydrate (Tm =142.9°C), form (II) anhydrate (Tm = 184.7°C ) and amorph (II) (Tg = 118°C) respectively. The attempts to produce amorph (I) from melting (in vicinity of form (I) melt over temperature range 133°C to 144°C) and supercooling was unsuccessful due to the high crystallization tendency of the form (I) melt. Brief humidity exposure and controlled temperature (40°C)/ humidity storage for 4 days (0-96% RH) revealed hygroscopic behaviour for the anhydrate crystal (forms (I) and (II)) and amorph (II) forms. Form (II) converted to a nonstoichiometric hydrate where extent of water vapour absorption increased with increased storage humidity (2.1% absorbed moisture from recorded TGA at 96% RH). Amorph (II) exhibited similar trends but with greater water absorption of 4.7% (recorded with TGA) at 96% RH. The pulverization and sieving process of amorph (II) (at normal environmental conditions) was accompanied by some water vapour absorption (1.1%). A slightly lower absorbed moisture content of 3.3% (from TGA) after controlled 4 days storage at 40°C/ 96% RH was recorded. This suggested some physical instability (crystallization tendency) of amorph (II) after pulverization. The thermally induced dehydration of RM-MH by DSC-TG was evaluated structurally (SCXRD), morphologically (microscopy) and by kinetic analysis. Various kinetic analysis approaches were employed (advanced, approximation based integral and differential kinetic analysis methods) in order to obtain reliable dehydration kinetic parameters. The crystal structure was little affected by dehydration as most H-bonds were intramolecular and not integral to the crystal structure stability. Kinetic parameters from thermally stimulated dehydration indicated a multidimensional diffusion based mechanism, due to the escape of water from interlinked voids in crystal. The hygroscopicity of the forms RM-MH, Roxithromycin-anhydrate and amorph glass (Tg = 81.4°C) were investigated. Roxithromycinanhydrate (crystalline) converted readily to RM-MH which were found to be compositionally stable over the humidity range 43-96%RH. Amorphous glass exhibited increased water vapour absorption with increasing storage humidity (40°C/ 0-96% RH). TG analysis suggested a moisture content of 3.5% at 96% RH after 4 storage days. DSC and powder XRD analysis of stored pulverised amorphous glass indicated some physical instability due to water induced crystallization. Commercial AZM-DH and its modifications were characterized by thermal analysis (DSC, TGA), SC-XRD and microscopy. Thermally stimulated dehydration of AZM-DH occurred in a two-step process over different temperature ranges. This was attributed to different bonding environments for coordinated waters which were also verified from the crystal structure. Dehydration activation energies for thermally stimulated dehydration were however similar for both loss steps. This was attributed to similarities in the mode of H- bonding. Different forms of AZM were prepared by programmed temperature heating and cooling of AZM-DH. The prepared forms included amorphous glass (melt supercooling), amorphous powder (prepared below crystalline melting temperature), crystalline anhydrate and crystalline partial dehydrate. Humidity exposure indicated hygroscopic behaviour for the amorphous, crystalline anhydrate and crystalline partial dehydrate modifications. Both the crystalline anhydrate and partial dehydrate modifications converted to the stoichiometric dihydrate form (AZM-DH) at normal environmental conditions at ambient temperature. Both the amorph glass and amorph powder exhibited increased moisture absorption with increased humidity exposure. TG analysis of the pulverised amorph glass indicated a moisture content of 5.1% at 96% RH after 4 storage days. The absence of crystalline melt in DSC and presence of Tg (106.9°C) indicated the sample remained amorphous after pulverisation and storage for 4 days at 40°C/ 96% RH.
  • Full Text:
  • Date Issued: 2016

Physicians' perspectives on personal health records: a descriptive study

  • Authors: Harmse, Magda Susanna
  • Date: 2016
  • Subjects: Medical records -- Data processing , Medical records -- Management , Information storage and retrieval systems -- Hospitals , Personal information management
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: http://hdl.handle.net/10948/6876 , vital:21156
  • Description: A Personal Health Record (PHR) is an electronic record of a patient’s health-related information that is managed by the patient. The patient can give access to other parties, such as healthcare providers and family members, as they see fit. These parties can use the information in emergency situations, in order to help improve the patient’s healthcare. PHRs have an important role to play in ensuring that a patient’s complete health history is available to his healthcare providers at the point of care. This is especially true in South Africa, where the majority of healthcare organizations still rely on paper-based methods of record-keeping. Research indicates that physicians play an important role in encouraging the adoption of PHRs amongst patients. Whilst various studies have focused on the perceptions of South African citizens towards PHRs, to date no research has focused on the perceptions of South African physicians. Considering the importance of physicians in encouraging the adoption of PHRs, the problem being addressed by this research project thus relates to the lack of information relating to the perceptions of South African physicians of PHRs. Physicians with private practices at private hospitals in Port Elizabeth, South Africa were surveyed in order to determine their perceptions towards PHRs. Results indicate perceptions regarding benefits to the physician and the patient, as well as concerns to the physician and the patient. The levels of trust in various potential PHR providers and the potential uses of a PHR for the physician were also explored. The results of the survey were compared with the results of relevant international literature in order to describe the perceptions of physicians towards PHRs.
  • Full Text:
  • Date Issued: 2016

Physicochemical and antimicrobial photodynamic chemotherapy of unsymmetrical indium phthalocyanines alone or in the presence of magnetic nanoparticles

  • Authors: Osifeko, Olawale L , Uddin, Imran , Mashazi, Philani N , Nyokong, Tebello
  • Date: 2016
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/189121 , vital:44818 , xlink:href="https://doi.org/10.1039/C5NJ01922B"
  • Description: An AB3 type photosensitiser, consisting of 4-pyridylsulfanyl units (denoted as B3) and one aminophenoxy (denoted as A) group (complex 3) was synthesized. Complex 3 was then quaternized to form complex 4. The aminophenoxy substituent of complex 3 was used for the formation of the amide linkage with the carboxylic functionalised magnetic nanoparticles. Complexes 3 and 4 and their conjugates with magnetic nanoparticles were then used for photodynamic antimicrobial chemotherapy on E. coli. The cationic photosensitiser 4 showed a high efficiency for photodynamic antimicrobial chemotherapy at a very low concentration compared to its conjugate on E. coli.
  • Full Text:
  • Date Issued: 2016

Pitched

  • Authors: Du Plessis, Jana
  • Date: 2016
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:6002 , http://hdl.handle.net/10962/d1021209
  • Description: Pitched is a novella made up of short stories. It is about breaking in, breaking down and breaking out of the advertising industry. My protagonist loves and hates this confusing world she lives in. She is tough but also emotional and anxious, often trapped between her strong desires and her strong morality. She finds herself both attracted to and repulsed by the people who inhabit this world - sexy wolf-like men, and prickly female execs alike. I have been inspired by the work of Lidia Yuknavitch, Kate Zambreno, Michelle Tea and Chris Kraus to create a universal woman I can identify with.
  • Full Text:
  • Date Issued: 2016

Planning adaptation to climate change in fast-warming marine regions with seafood-dependent coastal communities

Plasmodium falciparum Hep1 is required to prevent the self aggregation of PfHsp70-3

  • Authors: Nyakundi, David O , Vuko, Loyiso A M , Bentley, Stephen J , Hoppe, Heinrich C , Blatch, Gregory L , Boshoff, Aileen
  • Date: 2016
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/66109 , vital:28903 , https://doi.org/10.1371/journal.pone.0156446
  • Description: publisher version , The majority of mitochondrial proteins are encoded in the nucleus and need to be imported from the cytosol into the mitochondria, and molecular chaperones play a key role in the efficient translocation and proper folding of these proteins in the matrix. One such molecular chaperone is the eukaryotic mitochondrial heat shock protein 70 (Hsp70); however, it is prone to self-aggregation and requires the presence of an essential zinc-finger protein, Hsp70-escort protein 1 (Hep1), to maintain its structure and function. PfHsp70-3, the only Hsp70 predicted to localize in the mitochondria of P. falciparum, may also rely on a Hep1 orthologue to prevent self-aggregation. In this study, we identified a putative Hep1 orthologue in P. falciparum and co-expression of PfHsp70-3 and PfHep1 enhanced the solubility of PfHsp70-3. PfHep1 suppressed the thermally induced aggregation of PfHsp70-3 but not the aggregation of malate dehydrogenase or citrate synthase, thus showing specificity for PfHsp70-3. Zinc ions were indeed essential for maintaining the function of PfHep1, as EDTA chelation abrogated its abilities to suppress the aggregation of PfHsp70-3. Soluble and functional PfHsp70-3, acquired by co-expression with PfHep-1, will facilitate the biochemical characterisation of this particular Hsp70 protein and its evaluation as a drug target for the treatment of malaria. , This work was funded by grants from the National Research Foundation (NRF); grant number 87663 and Deutsche Forschungsgemeinschaft (DFG); grant number LI 402/14-1. D.O.N. is the recipient of academic development and training funds from Mwenge Catholic University, Moshi, Tanzania. S.J.B. is the recipient of an NRF Doctoral Innovation Scholarship.
  • Full Text:
  • Date Issued: 2016

Plasmodium falciparum Hsp70-z, an Hsp110 homologue, exhibits independent chaperone activity and interacts with Hsp70-1 in a nucleotide-dependent fashion

  • Authors: Ziningwa, Tawanda , Achilonu, Ikechukwu , Hoppe, Heinrich C , Prinsloo, Earl , Dirr, Heinrich W , Shonhai, Addmore
  • Date: 2016
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/431765 , vital:72802 , xlink:href="https://doi.org/10.1007/s12192-016-0678-4"
  • Description: The role of molecular chaperones, among them heat shock proteins (Hsps), in the development of malaria parasites has been well documented. Hsp70s are molecular chaperones that facilitate protein folding. Hsp70 proteins are composed of an N-terminal nucleotide binding domain (NBD), which confers them with ATPase activity and a Cterminal substrate binding domain (SBD). In the ADPbound state, Hsp70 possesses high affinity for substrate and releases the folded substrate when it is bound to ATP. The two domains are connected by a conserved linker segment. Hsp110 proteins possess an extended lid segment, a feature that distinguishes them from canonical Hsp70s.
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  • Date Issued: 2016

Politics at a distance from the state: radical, South African and Zimbabwean praxis today

  • Authors: Helliker, Kirk D , Van der Walt, Lucien
  • Date: 2016
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/71364 , vital:29837 , https://doi.org/10.1080/02589001.2016.1240792
  • Description: For decades, most anti-capitalist and anti-imperialist movements identified radical social transformation with the capture of state power. The collapse of supposedly enabling states led recently to a crisis of left and working class politics. But this has also opened space for the rediscovery of society-centred, anti-capitalist modes of bottom-up change, labelled as ‘at a distance’ politics. These modes have registered important successes in practice, such as the Zapatistas in Mexico, and have involved strands of anarchism and syndicalism, and autonomist Marxism. This article, an introduction to a collection of papers emerging from a 2012 conference of academics and activists in South Africa, aims to help articulate an understanding of social transformation from below that has been analytically and politically side-lined not only in South Africa (and Zimbabwe), but globally. In doing so, it provides a preliminary attempt to map and create a dialogue between three major positions within the broad category of ‘at a distance’ politics.
  • Full Text: false
  • Date Issued: 2016
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