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An understanting of mirrors and mirroring in a schizophrenic patient obsessed with his appearance

  • Authors: Zworestine, Barry John
  • Date: 1993-04
  • Subjects: Uncatalogued
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10962/191702 , vital:45149
  • Description: This work addresses the role of mirroring and mirrors encountered while working with a patient obsessed with his appearance. At the same time, however, it also attempts to provide an understanding of the process of mirroring from the developing unborn child to the adult. It examines the womb as a reflective space, the mirroring role of the mother, psychological work as mirror work, the psychopathologies of disruptive mirroring and the nature of reflection as a story, confusion and a ghostly other, and finally, the relationship between mirror reflection and psychological life. What is examined and described in this process applies not only to the specific case in study but is relevant at a universal level to all of mankind regardless of race or religion. The case-study method was used to examine the process of therapy that took place over three months. The patient’s identifying data, reasons for referral, presenting problem, family background, basic personality, interpersonal relationships, mental state, diagnosis, dynamic formulation and rationale for psychotherapy were covered in detail. The process of psychotherapy over 27 sessions was recounted and discussed in detail. Theoretical understandings drawn on to facilitate an understanding of the case were from Davis and Walbridge on Winnicolt, Winnicot, Liedloff, Kay, Romanyshyn, Bettelheim, Schwartz and others. , Thesis (MA) -- Faculty of Humanities, Psychology, 1993
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  • Date Issued: 1993-04

Aetiological factors that lead to suicide attempts among the youth of Lusikisiki area

  • Authors: Zweni, Mzamile Benute
  • Date: 2022-10
  • Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/27544 , vital:69314
  • Description: The general aim of this study was to investigate the aetiological factors that lead to suicidal attempts among the youth of Lusikisiki area in the Eastern Cape Province. A sample of hundred and fifty participants with an average age of 24 years old was selected using convenient sampling. Data was collected using self-administered questionnaires. After the data were collected, it was then analysed through descriptive and inferential statistics. Findings show that various factors lead to suicide ideation and suicide attempts among youth of Lusikisiki. Economic hardship, depression and substance abuse to name few, were found to be among factors that lead to suicide attempt. Based on the research findings, the researcher recommends that various stakeholders such as the Department of Social development should work in corroboration. Departments such as Department of Education and Sports, Recreation and Culture should make awareness campaigns that will psycho-educate youth in rural areas, possibly alleviating drug and substance abuse. Those awarenesses may also tap into strengthening psychosocial well-being of youth. Furthermore, Department of Social Development should come up with community outreach programs aimed at alleviating poverty as the contributory factor towards suicide attempt. , Thesis (MSoc) -- Faculty of Social Sciences and Humanities, 2022
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  • Date Issued: 2022-10

Mental healthcare users’ perceptions of mental health services at a primary healthcare level

  • Authors: Zwane, Siphelele
  • Date: 2025-04-25
  • Subjects: Mental health services South Africa Makhanda , Primary care (Medicine) , Mental health consumer , Mental health education South Africa , Help-seeking
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/478372 , vital:78181
  • Description: This study interrogates the complexities of mental healthcare in primary healthcare settings, focusing on the experiences and perceptions of participants within the Makana municipality in the Eastern Cape Province, which is characterised by a low socio-economic status. The matter of mental healthcare is of great significance within the context of South Africa, a country grappling with multifaceted challenges. Over the years, mental health has progressed from being marginalised to being more widely acknowledged. While the integration into tertiary and urban healthcare settings has become smoother, primary healthcare has encountered numerous obstacles. This presents a concern, due to the socioeconomic difficulties faced by individuals accessing primary care, which predispose them to mental health issues. Consequently, it is imperative to conduct research focusing on the experiences and perspectives of mental healthcare users within primary healthcare, a relatively underexplored area. The primary objective of the current research study was to contribute to the existing knowledge base, providing valuable insights for relevant stakeholders and policymakers, such as the National Mental Health Policy Framework 2023-2030, to reference when formulating strategies to enhance the integration of mental healthcare into primary healthcare. The study used purposive sampling to interview mental healthcare users within the Makana municipality. Employing a qualitative design facilitated in-depth dialogue between the participants and the researcher, generating valuable data. Thematic Analysis was employed to analyse and present meaningful data, providing an overview of the participants' shared experiences. The study identified four significant themes: the utility of primary health clinic; the urgent need for mental health education; socioeconomics, and mental health, and the complex dynamics of help-seeking behaviours. The findings underscore the pressing need to integrate quality mental health into PHC, emphasising the importance of mental health education, increased resources, task-sharing, and the prioritisation of both physical and mental illnesses. , Thesis (MA) -- Faculty of Humanities, Psychology, 2025
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  • Date Issued: 2025-04-25

Leveraging LTSP to deploy a sustainable e-infrastructure for poor communities in South Africa

  • Authors: Zvidzayi, Tichaona Manyara
  • Date: 2022-10-14
  • Subjects: Linux Terminal Server Project , Network computers , Thin client , Fat client , Cyberinfrastructure , Poverty reduction
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/365577 , vital:65761
  • Description: Poverty alleviation is one of the main challenges the South African government is facing. Information and knowledge are key strategic resources for both social and economic development, and nowadays they most often rely on Information and Communication Technologies (ICTs). Poor communities have limited or no access to functioning e-infrastructure, which underpins ICT. The Siyakhula Living Lab (SLL) is a joint project between the universities of Rhodes and Fort Hare that has been running for over 15 years now. The SLL solution is currently implemented in schools in the Eastern Cape’s Dwesa-Mbhashe municipality as well as schools in Makhanda (formerly Grahamstown). Over the years, a number of blueprints for the meaningful connection of poor communities was developed. The research reported in this thesis sought to review and improve the Siyakhula Living Lab (SLL) blueprint regarding fixed computing infrastructure (as opposed to networking and applications). The review confirmed the viability of the GNU/Linux Terminal Server Project (LTSP) based computing infrastructure deployed in schools to serve the surrounding community. In 2019 LTSP was redesigned and rewritten to improve on the previous version. Amongst other improvements, LTSP19+ has a smaller memory footprint and supports a graphical way to prepare and maintain the client’s image using virtual machines. These improvements increase the potential life of ICT projects implementing the SLL solution, increasing the participation of members of the community (especially teachers) to the maintenance of the computing installations. The review recommends the switching from thin clients deployments to full ("thick") clients deployments, still booting from the network and mounting their file systems on a central server. The switch is motivated by reasons that go from cost-effectiveness to the ability to survive the sudden unavailability of the central server. From experience in the previous deployment, electrical power surge protection should be mandatory. Also, UPS to protect the file system of the central server should be configured to start the shutdown immediately on electrical power loss in order to protect the life of the UPS battery (and make it possible to use cheaper UPS that report only on network power loss). The research study contributed to one real-life computing infrastructure deployment in the Ntsika school in Makhanda and one re-deployment in the Ngwane school in the Dwesa-Mbhashe area. For about two years, the research also supported continuous maintenance for the Ntsika, Ngwane and Mpume schools. , Thesis (MSc) -- Faculty of Science, Computer Science, 2022
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  • Date Issued: 2022-10-14

LTSP Client Image Maintenance: Utilising a Virtualisation Player to Support Educators to Directly Manage Classroom Applications

  • Authors: Zvidzayi, Tichaona , Terzoli, Alfredo , Dlodlo, Nomusa
  • Date: 2021
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/474364 , vital:77705 , xlink:href="https://ieeexplore.ieee.org/abstract/document/9576935"
  • Description: This paper reports on the work done in the Siyakhula Living Lab (SLL) schools, a joint project between the Universities of Rhodes and Fort Hare. The computing infrastructure in SLL is based on the Linux Terminal Server Project (LTSP), which allows client computers to boot from a centralised server and in some cases offload the computation to the server. Most SLL educators find it difficult to manage classroom applications using the GNU/Linux tools directly. So, educators had to rely on others to add applications for their classroom activity, reducing their sense of being in control and making processes longer and less flexible. A recent development in LTSP has introduced the possibility of setting the boot image for the clients within a virtual machine. This paper explores this option in detail and proposes that educators switch to a virtualisation player to manage applications they want to use in the classroom.
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  • Date Issued: 2021

Aspects of the ecology of the estuarine round-herring Gilchristella aestuaria (Pisces: Clupeidae) and its small-scale fishery potential

  • Authors: Zvavahera, Munetsi https://orcid.org/0000-0002-5337-1943
  • Date: 2021-05
  • Subjects: Small-scale fisheries , Silversides
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10353/22765 , vital:52752
  • Description: In the past two decades, there has been increasing pressure for small-scale inland fisheries to play a central role in food and nutrient security for poor communities in South Africa. For decades, South African inland fisheries have focussed on the exploitation of large fish species and generally ignored the exploitation of inland small fish species (SFS). This research aimed to assess the ecology and small-scale fishery potential of the estuarine round-herring, Gilchristella aestuaria. To understand the ecology of G. aestuaria better, morphometric trait analysis and fish condition of populations in relation to environmental variables (salinity, pH, temperature, turbidity and chlorophyll-a) were done. Fish were supplemented with samples acquired from the SAIAB collection facility for 14 sites to cover all the three South African biogeographic regions, stretching from Lake Sibaya (KZN) to the Orange River estuary in the western parts of the country. The morphometric trait analysis showed that G. aestuaria populations can be distinguished based on the trait variation, however there were many overlaps for populations that are interconnected, with distant/ geographically separated populations showing clear differences. Morphometric traits of the G. aestuaria population were significantly different, however there was no strong directional relationship with environmental variables and variation in morphometric traits. However, fish condition as measured by Fulton’s condition (K) and relative weight (Wr) showed variation between populations found in different environments. These differences suggest that these populations must be managed differently if G. aestuaria is to be exploited in managed fisheries. To determine the potential nutrient value of G. aestuaria to the human diet, samples from two freshwater sites and five estuarine sites were analysed for essential macro and micronutrients. The nutrient content of G. aestuaria revealed there is potential for exploitation, as the species has a high macro (protein and fat) and micronutrient composition (calcium, iron and zinc). Mean ± SD of selected nutrients were protein (61.7±5.0 g/100g), fat (20.4±3.7g/ 100g), calcium (3507.5±314.0mg), iron (40.37±14.0mg/ 100g), zinc (22.47±5.6mg/ 100) and vitamin A (37.3±44.4 RAE/ 100g). The nutrient composition of fish collected from freshwater sites was comparable to those collected from estuarine environments. Using the recommended dietary allowances (RDA) from literature, the mass of fish and the number of fish that would provide a minimum amount for each nutrient were calculated. A child would require only 13.4g of dry G. aestuaria or approximately 74 dried fish to meet the daily requirements of zinc. Other minerals such as iron and calcium also showed a similar low weight or number of fish required to meet daily requirements for the different categories. A small number of G. aestuaria are needed to meet RDA for groups (children, adult men, adult women, pregnant women and lactating mothers). A comparison was done for the nutrient composition of G. aestuaria with reference species that are already harvested for human consumption in some African and Asian countries. The protein content of G. aestuaria was comparable to Chisense (Microthrissa moeruensis) and Kapenta Limnothrissa miodon), while the fat composition was more than twice Chisense and Kapenta. Comparing the mineral composition, G. aestuaria had more than three times higher calcium than Mola (Amblypharyngodon mola) and Puti (Puntius sophore). Zinc composition was four times higher than M. moeruensis and L. miodon. Further exploration of the ecology of G. aestuaria was studied using the Sundays River irrigations ponds as a case study that would represent small impoundments across South Africa. Species rank abundance curve and catch per unit effort (CPUE) on the Sundays Irrigation ponds revealed that G. aestuaria dominated numerically and biomass in the Sundays River irrigation ponds. To assess the potential of harvesting G. aestuaria harvesting experiments were conducted using depletion (removal) sampling. Catchweight (kg) ranged from 2.16 (1.03; 3.28) to 61.25 (44.40; 78.09) kg and the estimated biomass from the depletion model ranged from 1.05 to 40.19 kg/ha for September 2019. The depletion model revealed that small impoundments have high biomass per hectare of G. aestuaria ranging from which indicates that the species may not support a commercial fishery but small-scale fisheries. In conclusion, G. aestuaria could become a meaningful contribution to the food and nutrient security of poor communities where available as a food source through small-scale fishery exploitation. The extent of this contribution may depend on its production potential in various regions and environments. More research is however needed to determine the long-term sustainability of harvesting of G aestuaria by looking at how populations respond to harvesting. , Thesis (PhD) -- Faculty of Science and Agriculture, 2021
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  • Date Issued: 2021-05

Challenges facing teachers in implementing alternative measures of discipline in schools: a case study of five secondary schools in the Umzimkhulu circuit of the Sisonke District in Kwazulu-Natal

  • Authors: Zulu, Xolani Wycliff
  • Date: 2014
  • Subjects: School discipline , Secondary schools , Sisonke District -- Kwazulu-Natal, South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/11260/2393 , vital:41455
  • Description: This dissertation is a report on a study that was conducted in rural schools of the Sisonke District in KwaZulu-Natal, a province of South Africa. The study covered the challenges experienced by teachers in implementing the alternative measures of discipline. The study was conducted because the researcher was the head of the disciplinary committee in the school where he was employed and he often dealt with disciplinary problems which usually occurred between the teachers, learners and SMTs. It was important to know from other schools, what problems they faced in implementing the alternative measures of discipline. The study used a qualitative research design in the form of a case study. Purposive sampling was used. The sample comprised 15 SMT members, and 20 post level 1 teachers, and the total number of participants was 35. Data was collected through observations which were followed by interviews. Qualitative methods were used to analyse data. This involved reduction and interpretation of data collected. The findings of the study highlighted the role that could be played by SMTs, teachers, parents, and the Department of Education in the smooth running of the school in dealing with the misunderstandings of alternative measures of discipline and so advance an effective work ethos. The study also illuminated the issue of negligence on the part of SMTs in enforcing the implementation of the alternative measures of discipline. There was a great need for school teachers to be well versed in the general legislation of the Department of Education so as to align themselves with the correct rules and regulations when they deal with disciplinary problems. , Thesis (MEd) -- Faculty of Humanities, Educational Management and Policy, 2014
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  • Date Issued: 2014

Synthesis, characterization and antibacterial studies of metal complexes of substituted thiourea

  • Authors: Zulu, Happy Nonkululeko
  • Date: 2012-03
  • Subjects: Complex compounds , Halides , Ligands
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/24327 , vital:62636
  • Description: Eighteen complexes Co(II), Cu(II), Zn(II), and Fe(III) with phenylthiourea, diethylthiourea, disopropylthiourea and dimethylthiourea were synthesized and characterized by elemental analysis, UV-Vis, FTIR, conductivity measurements. The complexes were formulated as either four coordinate for the metal(II) or six coordinate for Fe(III). The proposed formulations are consistent with the spectroscopic data for the complexes. The single crystal X-ray structure of the Zn(II) complex of phenylthiourea, Co(II) complex of diethylthiourea and Zn(II) complex of diisopropylthiourea are also reported. The X-ray crystal structures for these complexes revealed distorted tetrahedral geometry around the metal ions showed that the metal ions are coordinated to two molecules of the substituted thiourea through the sulphur atom and two either acetates or chlorides ions complete the four-coordinate geometry. The in vitro antibacterial activity of the complexes was studied against six bacterial strains using disc diffusion and broth micro-dilution methods. The complexes showed selective antibacterial activity. , Thesis (MSc) -- Faculty of Science and Agriculture, 2012
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  • Date Issued: 2012-03

Synthesis, characterization and antiparasitic evaluation of chalcone hybrids

  • Authors: Zulu, Ayanda Ignatia
  • Date: 2021-10-29
  • Subjects: Uncatalogued
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/192853 , vital:45271
  • Description: Thesis (PhD) -- Faculty of Science, Chemistry, 2021
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  • Date Issued: 2021-10-29

Perceptions of Kwazulu-Natal radiographers regarding the role of professional development in clinical practice

  • Authors: Zulu Anelisa
  • Date: 2022-12
  • Subjects: Radiography -- KwaZulu Natal , radiographers regarding
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/60290 , vital:64292
  • Description: Professional development in the form of continuing education is associated with professional competence and good service delivery to the patient, and this understanding of professional development applies to the radiography profession. A manager may prompt participation in professional development, or the needs of a radiography department may influence it, or it may be driven by the personal and professional ambitions of the radiographer. Participation could also be due to regulatory body requirements, which require tracking and documentation as in the case of the Health Professions Council of South Africa (HPCSA) which may audit the professional’s continuing professional development (CPD) compliance. Professional development is a concept inclusive of all learning such as CPD; postgraduate qualifications; staff development; and reflective practice, pursued for the betterment of the radiographers’ professional expertise. Few if any qualitative studies have sought to explore South African radiographers’ perceptions of professional development as a concept inclusive of all learning. The purpose of the study was to explore and describe the perceptions of KwaZulu-Natal radiographers regarding the role of professional development in clinical practice to make recommendations to radiography managers on how to optimise the participation of radiographers in professional development. Bandura’s social learning theory was used as the theoretical framework for a study of the perceptions of practising KZN radiographers regarding the role of professional development in clinical practice and exploring how people learn from one another, including concepts such as observational learning, imitation, and modelling. The target population for the study consisted of practising radiographers working in the public and private, rural and urban hospitals in KZN. Data were gathered using semi-structured one-on-one interviews and were coded using Tesch’s eight steps. The trustworthiness of this study was enhanced using Lincoln and Guba’s (1985) model of trustworthiness, namely: credibility, transferability, dependability and confirmability. , Thesis (MA) -- Faculty of Health Sciences, 2022
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  • Date Issued: 2022-12

The nexus between capital inflows, financial sector development and domestic investment in selected southern African development community countries

  • Authors: Zulani, Sihle https://orcid.org/0009-0006-7067-5793
  • Date: 2023-03
  • Subjects: Capital movements -- Africa, Southern , Saving and investment -- Africa, Southern , Financial services industry -- Africa, Southern
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/28872 , vital:75154
  • Description: The study seeks to examine the nexus between foreign capital inflows as proxied by foreign direct investment and overseas development assistance, financial sector development as measured by domestic credit to private sector and broad money supply (M3) and domestic investment [gross fixed capital formation] in selected Southern African Development Community (SADC) countries. Panel data model, specifically the panel Autoregressive Distributed Lag technique given the order of integration of the variables utilised in the study was employed from 1980 to 2019. The results revealed that there is cointegration among the variables utilised. After confirming cointegration, the long-run and short run models were estimated to establish the relationship between the variables. The long-run results revealed that about 67% of domestic investment in the SADC region is generated through foreign direct investment. These results suggest that domestic investment is boosted by foreign direct investment in the SADC region. However, financial sector development was found to have a negative effect on domestic investment in the SADC region. The findings from this study suggest that countries should pursue policies aimed at attracting FDI into the SADC region given the positive effect it has on investment. On the part of financial sector development, this could be attributed to the sector not supporting most of the domestic investment given that most of them are small and do not access bank finance. , Thesis (MCom) -- Faculty of Management and Commerce, 2023
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  • Date Issued: 2023-03

Comparative phototransformation of environmental pollutants using metallophthalocyanines supported on electrospun polymer fibers

  • Authors: Zugle, Ruphino , Nyokong, Tebello
  • Date: 2013
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/190509 , vital:45001 , xlink:href="https://doi.org/10.1002/app.38381"
  • Description: The fluorescence and photoactivity of a series of Zn and Lu phthalocyanine complexes incorporated in various polymer fibers were investigated for the phototransformation of 4-chlorophenol, 4-nitrophenol, and methyl orange. The phthalocyanine complexes functionalized on polystyrene and polysulfone polymer fibers could be applied in the degradation of 4-chlorophenol, 4-nitrophenol, and methyl orange with 4-chlorophenol being much more susceptible to degradation while methyl orange was the least. Also polymer fibers of polystyrene were found to be reusable.
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  • Date Issued: 2013

Zinc (II) 2, 9, 16, 23-tetrakis [4-(N-methylpyridyloxy)]-phthalocyanine anchored on an electrospun polysulfone polymer fiber: Application for photosensitized conversion of methyl orange

  • Authors: Zugle, Ruphino , Nyokong, Tebello
  • Date: 2013
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/232741 , vital:50020 , xlink:href="https://doi.org/10.1016/j.molcata.2012.10.001"
  • Description: In this work, a comparative study of photodegradation of methyl orange, an azo dye, in homogeneous aqueous solution of a quarternized cationic zinc phthalocyanine and a heterogeneous catalytic system based on the same phthalocyanine anchored on polysulfone polymer fiber is presented. In both cases, conversion involved the azo bond of the dye with no detectable opening up of the aromatic benzene rings. The reaction kinetics in both cases were consistent with first order with the conversion occurring in the homogeneous system being faster than when the functionalized polymer fiber was used. The reaction products consisted of a coupling product as well as a series of oligopolymeric products.
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  • Date Issued: 2013

Electrospun polyacrylic acid polymer fibers functionalized with metallophthalocyanines for photosensitizing and gas sensing applications

  • Authors: Zugle, Ruphino , Nyokong, Tebello
  • Date: 2012
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/243543 , vital:51162 , xlink:href="https://doi.org/10.1080/10601325.2012.662006"
  • Description: The photophysical and photochemical properties of tetraaminophthalocyanine complexes of lutetium and zinc covalently linked to polyacrylic acid were studied alongside those of unsubstituted zinc phthalocyanine within the same polymeric fiber matrix. All three phthalocyanines within the solid fiber matrices showed photoactivity by the generation of singlet oxygen as was observed in solution. The fluorescence behaviors of the composite fibers equally parallel those in solution. For the unsubstituted zinc phthalocyanine composite, the fiber showed fluorescence quenching on interaction with gaseous nitrogen dioxide similar to that in DMF and, thus could be a promising nanofabric material in developing optoelectronic devices that are responsive to the gas.
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  • Date Issued: 2012

Photophysical characterization of dysprosium, erbium and lutetium phthalocyanines tetrasubstituted with phenoxy groups at non-peripheral positions

  • Authors: Zugle, Ruphino , Litwinski, Christian , Nyokong, Tebello
  • Date: 2011
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/247561 , vital:51595 , xlink:href="https://doi.org/10.1016/j.poly.2011.03.030"
  • Description: Dysprosium bis-phthalocyanine and monomeric phthalocyanines of erbium and lutetium with non-peripheral phenoxy substituents have been synthesized using two different preparative routes. Photophysical studies on these phthalocyanines revealed that the triplet states of dysprosium and erbium are not populated while the monomeric phthalocyanine complex of lutetium is populated with a quantum yield of 0.83 and a lifetime of 25 μs in DMSO. It was further found that the phthalocyanine complex of lutetium was capable of photochemical generation of singlet state molecular oxygen with yield of 0.71 in THF, thus a promising photosensitizer. However, the three phthalocyanine molecules have very low fluorescence quantum yields of less than 0.01.
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  • Date Issued: 2011

Physico-chemical properties of lutetium phthalocyanine complexes in solution and in solid polystyrene polymer fibers and their application in photoconversion of 4-nitrophenol

  • Authors: Zugle, Ruphino , Nyokong, Tebello
  • Date: 2012
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/243520 , vital:51160 , xlink:href="https://doi.org/10.1016/j.molcata.2012.02.010"
  • Description: The photophysical and photochemical behavior of two phthalocyanine complexes of lutetium peripherally substituted with tetraphenoxy and tetra-2-pyridiloxy groups were studied in solution and when dispersed in polystyrene polymer fiber. The phthalocyanines were found not to fluoresce significantly in solution and not at all within the fiber matrix as compared with standard unsubstituted zinc phthalocyanine. They showed very promising photoactivity in solution with high singlet oxygen quantum yields. Their photoactivity within the polymer fiber matrix was also demonstrated with the photoconversion of 4-nitrophenol, a water pollutant. The photodegradation process with both phthalocyanines follows first order kinetics similar to that observed for the zinc phthalocyanine and the photo-products were found to be hydroquinone, benzoquinone and 4-nitrocatechol.
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  • Date Issued: 2012

Photooxidation of 4-chlorophenol sensitized by lutetium tetraphenoxy phthalocyanine anchored on electrospun polystyrene polymer fiber

  • Authors: Zugle, Ruphino , Antunes, Edith M , Khene, Samson M , Nyokong, Tebello
  • Date: 2012
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/245787 , vital:51405 , xlink:href="https://doi.org/10.1016/j.poly.2011.11.005"
  • Description: An electrospun polystyrene (PS) fiber incorporating tetraphenoxy phthalocyanine complex of lutetium (LuTPPc/PS) as a photosensitizer was applied for the degradation of 4-chlorophenol in aqueous solution in the presence of visible light. The photocatalytic activity of the LuTPPc in the fiber was compared to that of zinc phthalocyanine (ZnPc) incorporated into the PS fiber, and the former showed higher activity. UV–Vis spectral changes of sample solutions indicated transformation of the analyte with first order kinetics and half-lives that are within one and half hours for LuTPPc/PS. Products identified from the spectral changes and gas chromatography were benzoquinone, hydroquinone and 4,4′-dihydroxydiphenol suggesting that the photodegradation of 4-chlorophenol was through both Types I and II mechanisms.
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  • Date Issued: 2012

Photophysical and photochemical behavior of electrospun fibers of a polyurethane polymer chemically linked to lutetium carboxyphenoxy phthalocyanine

  • Authors: Zugle, Ruphino , Litwinski, Christian , Torto, Nelson , Nyokong, Tebello
  • Date: 2011
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/248428 , vital:51685 , xlink:href="https://doi.org/10.1039/C1NJ20126C"
  • Description: A phthalocyanine complex of lutetium substituted with four peripherally substituted 4-carboxyphenoxy groups was synthesized using cyclotetramerisation reaction. Its structure was elucidated using conventional spectroscopic methods and elemental analysis. The spectral behavior of the complex was studied in DMF solution and in a solid polyurethane fiber matrix. The UV-Visible spectrum showed a red shift in its Q-band maximum absorption within the fiber as compared to that in solution. The triplet quantum yield in DMF was determined to be 0.51 with a lifetime of 2.7 μs and a singlet oxygen quantum yield of 0.33 with a lifetime of 19.85 μs in the same solvent. The functionalized phthalocyanine fiber could be a promising fabric material for applications such as self-disinfecting in wound dressing. A method based on the conversion of ADMA was used to estimate the singlet oxygen quantum yield of the Pc in the hybrid fiber. An estimated singlet oxygen quantum yield value of 0.11 in aqueous medium was obtained. The fluorescence quantum yield of the Pc was found to be 0.01 with a lifetime of 3.20 ns in DMF.
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  • Date Issued: 2011

Determining the relationship between perceptions of HIV susceptibility and HIV status of women who have sex with women

  • Authors: Zuccarini, Aimee Frances
  • Date: 2024-10-11
  • Subjects: Teenage girls Attitudes , Young women Attitudes , Women who have sex with women , Stigma (Social psychology) , Informed consent (Medical law) , HIV infections Susceptibility
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/465859 , vital:76660
  • Description: Background: Adolescent girls and young women (AGYW) who have sex with women (WSW) are at potential risk for HIV, contradicting the common belief that WSW have low HIV susceptibility, a misperception persists despite evidence to refute it. Objective: This study examined the relationship between perceived HIV susceptibility and actual HIV status among South African AGYW WSW, focusing on those reporting at least one same-sex sexual experience, using data from the DREAMS Evaluation survey. Methods/Design: An archival study employing the Expanded Health Beliefs Model (EHBM) analysed secondary de-identified data from the DREAMS Evaluation Survey with a multistage stratified cluster sampling design. The sample comprised 18,296 AGYW aged 12-24 across four districts in South Africa, including 1,362 identified as WSW. ANOVA was conducted using SPSS 28 to explore the relationship between perceived HIV susceptibility and actual HIV status. Results: WSW’s perceived HIV susceptibility was low (38.5%) to very low (25%), while HIV prevalence in this sample/group was 15.9%. No significant relationship was found between perceived HIV susceptibility and actual HIV status (p = 0.126). Conclusions: WSW do not perceive themselves as being susceptible to contracting HIV despite the high prevalence of the virus in this group. Public health interventions should focus on raising awareness about risk factors, such as low use of barrier protection, substance use, and other behaviours highlighted in the literature, to better inform and protect this population. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
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  • Date Issued: 2024-10-11

The use of the cochineal insect, Dactylopius tomentosus Lamarck, as a biological control agent for the invasive alien thistle cholla, Cylindropuntia pallida (Rose) F.M. Knuth in South Africa

  • Authors: Zozo, Ekhona
  • Date: 2022-04-06
  • Subjects: Cochineal insect , Thistles Biological control South Africa , Alien plants South Africa , Invasive plants South Africa , Cactus South Africa , Biological assay
  • Language: English
  • Type: Master's thesis , text
  • Identifier: http://hdl.handle.net/10962/233823 , vital:50131
  • Description: Cylindropuntia pallida (Rose) F.M. Knuth (Cactaceae) is an invasive alien plant in South Africa indigenous in the southern U.S.A. and Mexico. Large infestations of this species can be found in the Kalahari and arid Karoo regions of South Africa, which is also present in Namibia. Because it is a very spiny cactus, dense infestations have a negative impact on agriculture and natural ecosystems. This cactus has become naturalised to the extent that eradication is impossible and the negative impacts are steadily increasing due to its increasing distribution and density. The cochineal insect, Dactylopius tomentosus Lamarck (Dactylopiidae), is native in Mexico and parts of North America, such as Texas, Arizona, and New Mexico in the U.S.A. This cochineal species is highly specialized and associated only with Cylindropuntia species, a group of cacti that are primarily restricted to the same areas. It has been introduced into Australia and South Africa as a biological control agent to control various invasive alien Cylindropuntia species. This cochineal species has several biotypes specific to certain Cylindropuntia species hosts. A biotype is a clade that cannot be differentiated morphologically from others but has different host ranges and impacts depending on the host plant species. Included amongst biotypes that have been released in South Africa are D. tomentosus ‘imbricata’ and D. tomentosus ‘cholla’ for the biological control of Cylindropuntia imbricata (Haw.) F.M. Knuth (Cactaceae) and Cylindropuntia fulgida (Engelmann) F.M. Knuth var. mamillata (Schott ex Engelmann) Backeb. (Cactaceae), respectively. These biotypes have resulted in both host plants being under substantial control in South Africa. The first part of this thesis evaluated which of the two D. tomentosus biotypes already in use in South Africa could be an effective biological control agent for C. pallida. This was done by assessing the fitness of the cochineals on the three cactus species and assessing the impact that each of the cochineals has on each of the target weed species. Should these biotypes prove ineffective, there is a third biotype, namely D. tomentosus ‘californica var. parkerii’, which researchers in Australia have worked on and have found to be suitably host-specific for release in Australia and suitably damaging to C. pallida in that country. Therefore, this new biotype could be released in South Africa if it is required. Sexually compatible biological control agents, especially those closely related and occurring in close spatial proximity to one another, may interbreed and the impacts of this hybridisation are difficult to predict. It is important to understand the outcomes of the hybridisation of cochineal because it can affect the impact of the biological control agents and thus the control of the target weed. The second part of this thesis investigated the impacts of the hybridisation of the two cochineal biotypes by assessing the damage the agents would have on the target weed, and on C. imbricata and C. fulgida var. mamillata, in the presence of one or both cochineal biotypes. The ‘cholla’ biotype performed better on C. pallida than the ‘imbricata’ biotype, but neither biotype could control C. pallida to an extent similar to the control they provide for their respective target weeds, C. imbricata and C. fulgida var. mamillata. Both the ‘cholla’ biotype and hybrids of the two biotypes of cochineal were effective at killing C. pallida when both C. imbricata and C. fulgida var. mamillata were also present. This suggests that the ‘cholla’ or hybrids may be effective at controlling C. pallida when either C. imbricata or C. fulgida var. mamillata are also present in the field due to the high population density of cochineal that results under these circumstances. There are, however, many C. pallida infestations in South Africa where the plant is problematic and is isolated from other Cylindropuntia species, and these populations are unlikely to be controlled by the ‘cholla’ biotype or the hybrids. Neither of the cochineal biotypes that are used for biological control in South Africa are suitably damaging to C. pallida to warrant their use as biological control agents for this species. Dactylopius tomentosus ‘californica var. parkerii’ is therefore recommended for release based on its host-specificity and impact to C. pallida in Australia. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2022
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  • Date Issued: 2022-04-06
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