List of Titles

The emancipatory potential of nursing practice in relation to sexuality: a systematic literature review of nursing research 2009–2014

- Macleod, Catriona I, Nhamo-Murire, Mercy

Authors: Macleod, Catriona I , Nhamo-Murire, Mercy
Date: 2016
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/446312 , vital:74489 , xlink:href="https://doi.org/10.1111/nin.12131"
Description: Nurses play a key role in the provision of services in relation to sexuality in both primary and sexual and reproductive health-care. Given the intersection of sexualities with a range of social injustices, this study reviews research on nursing practice concerning sexuality from an emancipatory/social justice perspective. A systematic review of English articles published in nursing journals appearing on the Web of Science database from 2009 to 2014 was conducted. Thirty-eight articles met the inclusion criteria. Analysis consisted of a descriptive phase (types and location of studies, aspects of sexualities focused on, target health users and aspects of nursing practice focused on) and a critical/emancipatory phase. In terms of practice, our analysis revealed that: barriers exist to the integration of issues relating to sexuality in nursing practice; the social location of nurses and their personal feelings regarding sexuality influence their practice; content that addresses gendered norms and media that assist in communication underpin some emancipatory practices. Few studies locate analyses of nursing practice within gendered, cultural and social norms; consider advocacy as part of the practice of nurses; or analyse the promotion of health user participation in health services and structures. The implications for emancipatory practice are drawn out.
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Date Issued: 2016

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The good African society index

- Botha, Ferdi

Authors: Botha, Ferdi
Date: 2016
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/396194 , vital:69157 , xlink:href="https://doi.org/10.1007/s11205-015-0891-z"
Description: This paper constructs a Good Society Index for 45 African countries, termed the Good African Society Index (GASI). The GASI consists of nine main indexes: (1) economic sustainability, (2) democracy and freedom, (3) child well-being, (4) environment and infrastructure, (5) safety and security, (6) health and health systems, (7) integrity and justice, (8) education, and (9) social sustainability and social cohesion. Each component is split into four sub-components for a total of 36 indicators. Tunisia ranks highest on the GASI, followed by Cape Verde and Botswana. Chad has the lowest GASI score, followed by Central African Republic and Cote d’Ivoire. The GASI is strongly related to the 2012 Human Development Index and Fragile States Index, to a lesser extent, GNI per capita.
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Date Issued: 2016

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The Guinea pigs of a problem-based learning curriculum

- Reddy, Sarasvathie, McKenna, Sioux

Authors: Reddy, Sarasvathie , McKenna, Sioux
Date: 2016
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/66730 , vital:28987 , ISSN 1470-3300 , https://doi.org/10.1080/14703297.2014.959542
Description: Publisher version , Participants in a study on learning the clinical aspects of medicine in a problem-based learning (PBL) curriculum repeatedly referred to themselves as ‘Guinea pigs’ at the mercy of a curriculum experiment. This article interrogates and problematises the ‘Guinea pig’ identity ascribed to and assumed by the first cohort of students who undertook a PBL curriculum. The article suggests that a range of issues may have come into play in the unfortunate events reported on here, and focuses on the participants’ reported experiences of marginalisation during their clinical education modules in the hospital wards. The impact of power differentials on identity formation was found to be exacerbated by the ‘Guinea pig’ characterisation.
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Date Issued: 2016

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The GULLS project: a comparison of vulnerabilities across selected ocean hotspots and implications for adaptation to global change

- Cochrane, Kevern L, Hobday, Alistair J, Aswani, Shankar, Byfield, Val, Dutra, Leo X C, Gasalla, Maria A, Haward, Marcus, Paytan, Adina, Pecl, Gretta T, Popova, Katya, Sainulabdeen, Shyam S, Savage, Candida, Sauer, Warwick H H, van Putten, Ingrid E, Visser, Natascha, TG Team

Authors: Cochrane, Kevern L , Hobday, Alistair J , Aswani, Shankar , Byfield, Val , Dutra, Leo X C , Gasalla, Maria A , Haward, Marcus , Paytan, Adina , Pecl, Gretta T , Popova, Katya , Sainulabdeen, Shyam S , Savage, Candida , Sauer, Warwick H H , van Putten, Ingrid E , Visser, Natascha , TG Team
Date: 2016
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/422037 , vital:71906
Description: The GULLS project, `Global learning for local solutions: Reducing vulnerability of marine-dependent coastal communities' has been underway since October 2014. The project has been investigating six regional `hotspots': marine areas experiencing rapid warming. These are south-east Australia, Brazil, India, Solomon Islands, South Africa, and the Mozambique Channel and Madagascar. Rapid warming could be expected to have social, cultural and economic impacts that could affect these countries in different ways and may already be doing so. GULLS has focused on contributing to assessing and reducing the vulnerability of coastal communities and other stakeholders dependent on marine resources and to facilitate adaptation to climate change and variability through an integrated and trans-disciplinary approach. It includes participants from Australia, Brazil, India, Madagascar, New Zealand, South Africa, the United Kingdom and the United States of America. The research programme has been divided into six inter-linked components: ocean models, biological and ecological sensitivity analyses, system models, social vulnerability, policy mapping, and communication and education. This presentation will provide a brief overview of each of these components and describe the benefits that have resulted from the collaborative and transdisciplinary approach of GULLS. Following the standard vulnerability elements of exposure, sensitivity and adaptive capacity, the vulnerabilities of coastal communities and other stakeholders dependent on marine resources in the five hotspots will be compared using a set of indicators derived and populated from results of the research programme. The implications of similarities and differences between the hotspots for adaptation planning and options will be described.
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Date Issued: 2016

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The impact of geographical origin of two strains of the herbivore, Eccritotarsus catarinensis, on several fitness traits in response to temperature

- Ismail, Mohannad, Brooks, Margot

Authors: Ismail, Mohannad , Brooks, Margot
Date: 2016
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/66914 , vital:28999 , ISSN 0306-4565 , https://doi.org/10.1016/j.jtherbio.2016.07.008
Description: Publisher version , Adaptation to temperature changes is vital to reduce adverse effects on individuals, and some may present phenotypic changes, which might be accompanied with physiological costs in fitness traits. The objective of this study was to determine whether the two strains of the herbivore Eccritotarsus catarinensis, a biological control agent against water hyacinth in South Africa, differ in their responses to temperature according to their geographical origin. We experimentally quantified the responses of the two strains, at three constant temperatures: 20 °C, 25 °C and 30 °C, using laboratory cultures that originated from Brazil and Peru, where climates differ. Reproductive output, egg hatching rate, sex ratio and longevity were recorded at each temperature. Fitness traits for both strains were significantly reduced at 30 °C compared with 25 °C and 20 °C in two successive generations. Nonetheless, Peruvian individuals continued their development at 30 °C, whereas Brazilian individuals that succeeded in emerging did not continue their development. In contrast, sex ratio was unaffected by temperature. The Peruvian strain of E. catarinensis presented different phenotypes depending on temperature and was more adapted to extreme high temperature than the Brazilian strain. The tropical origin of the population induces the insect to tolerate the extreme high temperature. We suggest that the Peruvian strain could be better suited for release to control water hyacinth in nature, particularly in regions where temperature is high.
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Date Issued: 2016

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The influence of photoperiod on the reproductive physiology of the greater red musk shrew: Crocidura flavescens

- Hoole, C, McKechnie, Andrew E, Parker, Daniel M, Bennett, Nigel C

Authors: Hoole, C , McKechnie, Andrew E , Parker, Daniel M , Bennett, Nigel C
Date: 2016
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/70136 , vital:29624 , https://doi.org/10.1139/cjz-2015-0128
Description: Photoperiodism involves the use of both absolute measures of day length and the direction in which day length is changing as a cue for regulating seasonal changes in physiology and behaviour so that birth and lactation coincide with optimal resource availability, increasing offspring survival. Induced ovulation and opportunistic breeding is often found in species that are predominantly solitary and territorial. In this study, the photoperiodic reproductive responses of male greater red musk shrews (Crocidura flavescens (I. Geoffroy Saint-Hilaire, 1827)) were investigated in the laboratory. The presence of spermatozoa regardless of the light cycle, suggest that although the shrews are photoresponsive, they may be capable of breeding throughout the year. Significantly greater testicular volume and eminiferous tubule diameter following exposure to a short day-light cycle suggests that these animals may have breeding peaks that correspond to short days. The presence of epidermal spines on the penis indicates that the shrew is likely also an induced ovulator. Flexible breeding patterns combined with induced ovulation affords this solitary species the greatest chance of reproductive success.
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Date Issued: 2016

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The influence of photoperiod on the reproductive physiology of the greater red musk shrew: Crocidura flavescens

- Hoole, C, McKechnie, Andrew E, Parker, Daniel M, Bennett, Nigel C

Authors: Hoole, C , McKechnie, Andrew E , Parker, Daniel M , Bennett, Nigel C
Date: 2016
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/70157 , vital:29626 , https://doi.org/10.1139/cjz-2015-0128
Description: Photoperiodism involves the use of both absolute measures of day length and the direction in which day length is changing as a cue for regulating seasonal changes in physiology and behaviour so that birth and lactation coincide with optimal resource availability, increasing offspring survival. Induced ovulation and opportunistic breeding is often found in species that are predominantly solitary and territorial. In this study, the photoperiodic reproductive responses of male greater red musk shrews (Crocidura flavescens (I. Geoffroy Saint-Hilaire, 1827)) were investigated in the laboratory. The presence of spermatozoa regardless of the light cycle, suggest that although the shrews are photoresponsive, they may be capable of breeding throughout the year. Significantly greater testicular volume and eminiferous tubule diameter following exposure to a short day-light cycle suggests that these animals may have breeding peaks that correspond to short days. The presence of epidermal spines on the penis indicates that the shrew is likely also an induced ovulator. Flexible breeding patterns combined with induced ovulation affords this solitary species the greatest chance of reproductive success.
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Date Issued: 2016

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The inhibitory effects of various substrate pre-treatment by-products and wash liquors on mannanolytic enzymes

- Malgas, Samkelo, Van Dyk, J Susan, Abboo, Sagaran, Pletschke, Brett I

Authors: Malgas, Samkelo , Van Dyk, J Susan , Abboo, Sagaran , Pletschke, Brett I
Date: 2016
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/66156 , vital:28911 , https://doi.org/10.1016/j.molcatb.2015.11.014
Description: publisher version , Biomass pre-treatment is essential for achieving high levels of bioconversion through increased accessibility of hydrolytic enzymes to hydrolysable carbohydrates. However, pre-treatment by-products, such as sugar and lignin degradation products, can negatively affect the performance of hydrolytic (mannanolytic) enzymes. In this study, two monomeric sugars, five sugar degradation products, five lignin derivatives and four liquors from biomass feedstocks pre-treated by different technologies, were evaluated for their inhibitory effects on mannanolytic enzymes (α-galactosidases, β-mannanases and β-mannosidases). Lignin derivatives elicited the greatest inhibitory effect on the mannanolytic enzymes, followed by organic acids and furan derivatives derived from sugar degradation. Lignin derivative inhibition appeared to be as a result of protein–phenolic complexation, leading to protein precipitating out of solution. The functional groups on the phenolic lignin derivatives appeared to be directly related to the ability of the phenolic to interfere with enzyme activity, with the phenolic containing the highest hydroxyl group content exhibiting the greatest inhibition. It was also demonstrated that various pre-treatment technologies render different pre-treatment soluble by-products which interact in various ways with the mannanolytic enzymes. The different types of biomass (i.e. different plant species) were also shown to release different by-products that interacted with the mannanolytic enzymes in a diverse manner even when the biomass was pre-treated using the same technology. Enzyme inhibition by pre-treatment by-products can be alleviated through the removal of these compounds prior to enzymatic hydrolysis to maximize enzyme activity.
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Date Issued: 2016

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The interaction between graphene quantum dots grafted with polyethyleneimine and Au@ Ag nanoparticles

- Achadu, Ojodomo John, Uddin, Imran, Nyokong, Tebello

Authors: Achadu, Ojodomo John , Uddin, Imran , Nyokong, Tebello
Date: 2016
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/188679 , vital:44775 , xlink:href="https://doi.org/10.1016/j.jphotochem.2016.03.016"
Description: Graphene quantum dots grafted with polyethyleneimine (GQDs-PEI) and Au@Ag core-shell nanoparticles blend was demonstrated to be a novel biosensing nanoprobe for the rapid and highly sensitive detection of biothiols such as cysteine (Cys), homocysteine (Hcys) and glutathione (GSH). The fluorescence emission of GQDs-PEI was quenched efficiently upon interaction with Au@Ag core-shell nanoparticles. The quenched fluorescence emission of the GQDs-PEI was restored in the presence of the biothiols. The fluorimetric sensing is based on the strong affinity between the mercapto (SH) groups of the biothiols and the Au@Ag core-shell nanoparticles by which the interaction between GQDs-PEI and Au@Ag core-shell nanoparticles was disrupted with a consequent modulation (‘turn-on’) of the quenched GQDs-PEI emission. Thus, a new, simple, rapid and highly sensitive fluorescence nanoprobe for detecting biothiols has been developed in this work.
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Date Issued: 2016

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The last stop

- Mofokeng, Thabiso

Authors: Mofokeng, Thabiso
Date: 2016
Language: English
Type: text , Thesis , Masters , MA
Identifier: http://hdl.handle.net/10962/64567 , vital:28559
Description: My novella is set in the taxi industry. Its main characters are a wealthy taxi owner, a poor taxi driver from another African country, and the taxi driver's girlfriend. The story is partly a ghost story and partly crime fiction, it combines gritty realism with magical elements. It shows what happens between people in times of taxi violence. As the plot develops, the driver finds out that his boss is sleeping with his girlfriend. In revenge, the boss bribes some policemen to arrest the driver and beat him, and he dies in the police cells. But it turns out that the detective investigating the driver’s death is not quite impartial, nor is he of this world only.
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Date Issued: 2016

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The limitations of current health literacy measures for use in developing countries:

- Dowse, Roslind

Authors: Dowse, Roslind
Date: 2016
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/156607 , vital:40030 , DOI: 10.1080/17538068.2016.1147742
Description: Health literacy measures have largely emanated from developed countries, reflecting the characteristics of their economies, populations, and health systems. In contrast, it is disconcerting that health literacy appears to be so under-researched in developing countries (DCs), despite the likelihood of inadequate health literacy being endemic. In this commentary, I highlight some challenges when using existing health literacy measures in DCs and conclude with a summary of considerations when using/developing a tool for these populations.
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Date Issued: 2016

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The Malarial Exported PFA0660w Is an Hsp40 Co-Chaperone of PfHsp70-x

- Daniyan, Michael O, Boshoff, Aileen, Prinsloo, Earl, Pesce, Eva-Rachele, Blatch, Gregory L

Authors: Daniyan, Michael O , Boshoff, Aileen , Prinsloo, Earl , Pesce, Eva-Rachele , Blatch, Gregory L
Date: 2016
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/66098 , vital:28901 , https://doi.org/10.1371/journal.pone.0148517
Description: publisher version , Plasmodium falciparum, the human pathogen responsible for the most dangerous malaria infection, survives and develops in mature erythrocytes through the export of proteins needed for remodelling of the host cell. Molecular chaperones of the heat shock protein (Hsp) family are prominent members of the exportome, including a number of Hsp40s and a Hsp70. PFA0660w, a type II Hsp40, has been shown to be exported and possibly form a complex with PfHsp70-x in the infected erythrocyte cytosol. However, the chaperone properties of PFA0660w and its interaction with human and parasite Hsp70s are yet to be investigated. Recombinant PFA0660w was found to exist as a monomer in solution, and was able to significantly stimulate the ATPase activity of PfHsp70-x but not that of a second plasmodial Hsp70 (PfHsp70-1) or a human Hsp70 (HSPA1A), indicating a potential specific functional partnership with PfHsp70-x. Protein binding studies in the presence and absence of ATP suggested that the interaction of PFA0660w with PfHsp70-x most likely represented a co-chaperone/chaperone interaction. Also, PFA0660w alone produced a concentration-dependent suppression of rhodanese aggregation, demonstrating its chaperone properties. Overall, we have provided the first biochemical evidence for the possible role of PFA0660w as a chaperone and as co-chaperone of PfHsp70-x. We propose that these chaperones boost the chaperone power of the infected erythrocyte, enabling successful protein trafficking and folding, and thereby making a fundamental contribution to the pathology of malaria. , This work was supported by grants from the National Research Foundation (NRF) and Medical Research Council (MRC) of South Africa. The ProteOn XPR36 IAS was purchased from a National Nanotechnology Equipment Programme grant from the Department of Science and Technology and the NRF of South Africa. Michael O. Daniyan was a recipient of the Education Trust Fund (ETF) Academic Staff Training and Development (AST and D) scholarship of Obafemi Awolowo University, Ile-Ife, Nigeria and a Rhodes University Council research bursary
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Date Issued: 2016

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The network society: A model for computing infrastructure in South African schools

- Siebörger, Ingrid, Terzoli, Alfredo

Authors: Siebörger, Ingrid , Terzoli, Alfredo
Date: 2016
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/430651 , vital:72706 , 10.1109/ISTAFRICA.2016.7530673
Description: Worldwide computers are being used in schools for, amongst other things, developing the knowledge and skills required for citizens to be able to operate within the 21st Century Information Age. Realising the potential of technology in uplifting the lives of its citizens the South Afri-can government has proposed the National Broadband Plan (SA Con-nect). However, unfortunately this plan only addresses the networking aspect of Information Communication Technologies (ICTs). In this pa-per we investigate appropriate Information Technologies for schools in the light of SA Connect, and propose a model for the computing infra-structure required in South African schools in order to support access to and adoption of technology and networks. This model is based on our multi-year experimentation in the Siyakhula Living Lab.
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Date Issued: 2016

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The optical limiting of blue and green ytterbium double-decker phthalocyanines in solution and in poly (acrylic acid) as thin films

- Sekhosana, Kutloana E, Nyokong, Tebello

Authors: Sekhosana, Kutloana E , Nyokong, Tebello
Date: 2016
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/188585 , vital:44767 , xlink:href="https://doi.org/10.1016/j.ica.2016.05.026"
Description: Bis{1(4), 8(11), 15(18), 22(25)-tetra(4-tert-butylphenoxy)phthalocyaninato} ytterbium(III) (2a) (the green form) was synthesized and reduced to form 2b (the blue form). Nonlinear optical parameters for complex 2 in green and blue forms were determined using the Z-scan technique and the values of third-order imaginary susceptibility (Im[χ(3)]) and second-order hyperpolarizability (γ) of the order of 10−9 (for 2b) and 10−27 esu, respectively, were obtained in solution. In poly(acrylic acid) as a thin film, complex 2a showed extremely high Im[χ(3)] and γ values of the order 10−8 and 10−25 respectively. A low optical limiting threshold value of 0.075 J cm−2 was obtained for the thin film 2a.
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Date Issued: 2016

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The pattern-richness of graphical passwords

- Vorster, Johannes, Van Heerden, Renier, Irwin, Barry V W

Authors: Vorster, Johannes , Van Heerden, Renier , Irwin, Barry V W
Date: 2016
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/68322 , vital:29238 , https://doi.org/10.1109/ISSA.2016.7802931
Description: Publisher version , Conventional (text-based) passwords have shown patterns such as variations on the username, or known passwords such as “password”, “admin” or “12345”. Patterns may similarly be detected in the use of Graphical passwords (GPs). The most significant such pattern - reported by many researchers - is hotspot clustering. This paper qualitatively analyses more than 200 graphical passwords for patterns other than the classically reported hotspots. The qualitative analysis finds that a significant percentage of passwords fall into a small set of patterns; patterns that can be used to form attack models against GPs. In counter action, these patterns can also be used to educate users so that future password selection is more secure. It is the hope that the outcome from this research will lead to improved behaviour and an enhancement in graphical password security.
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Date Issued: 2016

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The photobleaching of the free and encapsulated metallic phthalocyanine and its effect on the photooxidation of simple molecules

- Fanchiotti, Brenda Gomes, Machado, Marcella Piffer Zamprogno, de Paula, Letícia Camilato, Durmuş, Mahmut, Nyokong, Tebello, da Silva, Gonçalves, da Silva, André Romero

Authors: Fanchiotti, Brenda Gomes , Machado, Marcella Piffer Zamprogno , de Paula, Letícia Camilato , Durmuş, Mahmut , Nyokong, Tebello , da Silva, Gonçalves , da Silva, André Romero
Date: 2016
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/239687 , vital:50755 , xlink:href="https://doi.org/10.1016/j.jphotobiol.2016.10.007"
Description: The photobleaching of an unsubstituted phthalocyanine (gallium(III) phthalocyanine chloride (GaPc)) and a substituted phthalocyanine (1,4-(tetrakis[4-(benzyloxy)phenoxy]phthalocyaninato) indium(III) chloride (InTBPPc)) was monitored for the free photosensitizers and for the phthalocyanines encapsulated into nanoparticles of PEGylated poly(D,L-lactide-co-glycolide) (PLGA-PEG). Phosphate-buffered solutions (PBS) and organic solutions of the free GaPc or the free InTBPPc, and suspensions of each encapsulated photosensitizer (2–15 μmol/L) were irradiated using a laser diode of 665 nm with a power of 1–104 mW and a light dose of 7.5 J/cm2. The relative absorbance (RA) of the free GaPc dissolved in 1-methyl-2-pyrrolidone (MP) decreased 8.4 times when the laser power increased from 1 mW to 104 mW. However, the free or encapsulated GaPc did not suffer the photobleaching in PBS solution. The RA values decreased 2.4 times and 22.2 times for the free InTBPPc dissolved in PBS solution and in dimethylformamide (DMF), respectively, but the encapsulated InTBPPc was only photobleached when the laser power was 104 mW at 8 μmol/L. The increase of the free GaPc concentration favored the photobleaching in MP until 8 μmol/L while the increase from 2 μmol/L to 5 μmol/L reduced the photodegradation in PBS solution. However, the photobleaching of the free InTBPPc in DMF or in PBS solution, and of each encapsulated photosensitizer was not influenced by increasing the concentration. The influence of the photobleaching on the capability of the free and encapsulated GaPc and InTBPPc to photooxidate the simple molecules was investigated monitoring the fluorescence of dimethylanthracene (DMA) and the tryptophan (Trp). Free InTBPPc was 2.0 and 1.8 times faster to photooxidate the DMA and Trp than it was the free GaPc, but the encapsulated GaPc was 3.4 times more efficient to photooxidize the Trp than it was the encapsulated InTBPPc due to the photodegradation suffered by the encapsulated InTBPPc. The participation of the singlet oxygen was confirmed with the sodium azide in the photobleaching of all free and encapsulated photosensitizer, and in the photooxidation of the DMA and Trp. The asymmetry of InTBPPc increased the solubility of the free compound, decreasing the aggregation state of the photosensitizer and favoring the photobleaching process. The encapsulation shows capability in decreasing the photobleaching of both photosensitizers but the confocal micrographs showed that the increase of the solubility favored the InTBPPc photobleaching during the acquisition of optical cross section. A novel low-symmetry A3B-type phthalocyanine annelated with a pyrazino[2,3-f]phenanthroline ring system and substituted with six solubilizing diisopropylphenoxy-groups (1) was synthesized by metalfree DBU-promoted cross-condensation of diiminoisoindolines derived from 4,5- bis(diisopropylphenoxy)phthalonitrile and pyrazino[2,3-f][1,10]phenanthroline-2,3-dicarbonitrile. The use of these particular precursors affords A3B phthalocyanine in 15% yield, while cross-condensation of the corresponding dinitriles yields only trace amounts of the target compound. Comparative studies of the A3B-type phthalocyanine and its symmetrical octa(diisopropylphenoxy)-substituted counterpart 2 reveal striking differences in the Q band regions of their UVevisible absorption (UVeVis) spectra, which could be readily rationalized through a comparison with calculated TD-DFT spectra. Since 1 can have two NH-tautomers with equivalent and non-equivalent NH-groups, and DFT calculations predict that the former tautomer is only 2.3 kcal/mol more stable than the latter one, a comprehensive analysis of 13C NMR spectra was carried out through the application of 1 He13C HMBC and HSQC techniques. It demonstrated that only the tautomer with equivalent NH-groups is present in solution.
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Date Issued: 2016

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The phytogeography of Southern Mistbelt Forests of the Eastern Cape, South Africa

- Matiwane, Aviwe

Authors: Matiwane, Aviwe
Date: 2016
Language: English
Type: text , Thesis , Masters , MSc
Identifier: http://hdl.handle.net/10962/3224 , vital:20393
Description: In the Eastern Cape, a moisture gradient (from west to east) exists along the Escarpment where patches of Southern Mistbelt Forests (SMF) occur. There is a notable profusion of plants in these forests, but the factors that drive plant species composition and abundance in these patches is poorly understood and such knowledge is critical if we are to address or mitigate the problems imposed by global change. Many of our ideas on plant community assembly are based on the premise that species differ in their environmental requirements for successful regeneration, especially when young. The aims of this study were to document the floristic diversity of poorly known patches of Southern Mistbelt Forests in the Eastern Cape and identify the environmental factors that influence plant community composition in these forest patches. Twenty six forest patches across the Eastern Cape were sampled. In each forest 400m2 circular plots were constructed. The diameter at breast height and stem counts for the tree species was taken and the % cover of the herbaceous species was recorded. General collections were also made to supplement the plot data in order to obtain a comprehensive flora for each forest patch. All sampling was done during the summer season of 2013 and 2014. Using plot data, Hierarchal Cluster Analysis and Multidimensional Scaling Analysis were done to compare similarities between patches. Plots from the same forest patch clustered which indicated that the species composition in each forest patch was unique. However, this pattern went down when only tree species were considered. Plant diversity also varied between patches; with those located in the east being generally more diverse than those in the west are. Clustering patterns in fragmented communities and differences in species diversity indicate evidence of species “nestedness”. Analysis of nestedness indicated that these forest patches were significantly nested. To identify which environmental variables might be correlated with both species diversity and nestedness, twelve environmental variables was selected for analysis using Canonical Correspondence Analysis and Principal Component Analysis. Results show that Mean Annual Precipitation, Mean Annual Potential Evapotranspiration, and percentage of Organic Matter of the soil were most strongly correlated with the patterns of diversity observed in these forest patches. Regression analysis indicated that Mean Annual Precipitation accounted for most of the variation in species diversity, especially for the herbaceous species. The herbaceous species thus show a greater sensitivity to “climate filtering” as a consequence of rainfall gradients. With the implementation of suitable monitoring programs, changes in abundance or even local extinction of these species can act as an early warning indicator of the possible long-term effects of climate change on forest communities.
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Date Issued: 2016

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The trophic ecology of waterbirds in a small temperate estuary: a stable isotope and lipid tracer approach

- Hean, Jeffrey William

Authors: Hean, Jeffrey William
Date: 2016
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/54356 , vital:26557
Description: Waterbirds are often overlooked as predators in aquatic ecosystems, despite the fact that waterbirds congregate in great numbers in and around waterways, notably estuaries. To fully appreciate the effect that aquatic feeding waterbird species may have on aquatic prey communities and the role that they play in estuarine food webs, stable isotopes and fatty acid profiles were employed to examine the seasonal diet of selected waterbirds in the Kowie Estuary, Eastern Cape Province, South Africa. Population counts were conducted every month for four seasons to examine the demography of waterbirds in the lower reaches of the estuary. The mean monthly energy consumption, along with dry matter intake of all waterbird species observed, were calculated and compared to similar estuaries in South Africa and elsewhere. Three duck species, one migrant sandpiper and one piscivore were selected for more detailed investigation at several temporal scales. This thesis has revealed that stable isotope analysis of waterbird tissues provides more informative data than fatty acid analysis for investigating waterbird diet and basal resource-tertiary consumer nutrient coupling. Stable δ15N and δ13C isotopes from several body tissues, in conjunction with SIAR models, were used to determine the seasonal diet of each waterbird species, while fatty acid profiles were investigated to examine the trophic transfer of fatty acids from basal resources to waterbird predators via the benthic fauna. Stable isotopes revealed that Cape Shoveller, Cape Teal and Yellow-Billed Duck shifted their diet over both long and short temporal scales, while the migratory Ruff and piscivorous Little Egret maintained a relatively consistent diet over time. Isopods, amphipods, copepods and Mysidacea were the main foods of all three duck species and the Ruff (>30%). Little Egret fed mainly on flathead mullet throughout the year. Fatty acid analysis revealed evidence for trophic transfer of specific fatty acids from basal resources to waterbirds in the Kowie Estuary but provided little information on seasonal diet of waterbirds. Waterbirds foraging in the Kowie Estuary appeared to shift their diet to coincide with resource abundance pulses, but also displayed seasonal dietary overlap. This study highlights the role that waterbirds play in aquatic food webs. The subject requires more attention so that we can better understand all the predatory drivers on aquatic communities.
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Date Issued: 2016

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Thermoluminescence of kunzite: a study of kinetic processes and dosimetry characteristics

- Ogundare, F O, Alatishe, M A, Chithambo, Makaiko L, Costin, G

Authors: Ogundare, F O , Alatishe, M A , Chithambo, Makaiko L , Costin, G
Date: 2016
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/124701 , vital:35650 , https://doi.org/10.1016/j.nimb.2016.02.059
Description: Since the use of natural minerals for dating and dose reconstruction using luminescence techniques is well-established and always of interest, we present thermoluminescence characteristics of kunzite, a gem variety of spodumene. The chemical composition of the sample was determined using an Electron Probe MicroAnalyzer.
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Date Issued: 2016

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