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A sea is brewing

- Mama, Sibongakonke

  • Authors: Mama, Sibongakonke
  • Date: 2022-10-14
  • Subjects: Creative writing (Higher education) South Africa , Xhosa poetry 21st century , South African poetry (English) 21st century , Psychic trauma in literature , Women in literature , Diaries -- Authorship , Books Reviews
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/406281 , vital:70255
  • Description: My thesis is a collection of poems that draws on the complexity of not belonging in places, with people, or within families. I engage my own alienation as well as that of my parents, black people generally, and women in particular. I take inspiration from Uruguayan poet Fabián Severo’s autobiographical long poem, Night in the North, which chronicles the poet’s experience of growing up in linguistic and cultural borderlands. I am also influenced by Chilean poet Carmen García’s ability to move between the concrete and the abstract in translations of her poems from the collection Gotas sobre loza fría. As much as my poems traverse a metaphysical space, they are also set in concrete places – Tutura, Gcuwa, Johannesburg, and Cape Town. Like Chilean artist Cecilia Vicuña’s Spit Temple, I move between the physical and spiritual realms for a better understanding of my estrangement. I also draw on South African poet Mangaliso Buzani’s book, a naked bone, for its fluid combination of line and prose poetry. I write in isiXhosa and English as a reflection of my mixed cultural and linguistic existence. I seek to harness rhythm and harmony, as well as the quiet, between words. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2022
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Chaos!

- Ngwenya, Thembalethu Sabrina

  • Authors: Ngwenya, Thembalethu Sabrina
  • Date: 2022-10-14
  • Subjects: Creative writing (Higher education) South Africa , Diaries -- Authorship , Books Reviews , South African prose literature (English) 21st century , South African fiction (English) 21st century
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/406298 , vital:70256
  • Description: Chaos! is a combination of short prose forms in fragments that tackles difficult topics such as troubled marriages, child molestation, rape, infidelity and abuse in every way, whether it is mental, emotional or physical. The stories contain a lot of horrific and violent acts that, often times in this day and age, happen behind closed doors or sometimes even openly, yet not a lot of people are ready to talk about these topics. In my thesis, I go into the minds of those that are abusive and those that are on the receiving end of abuse. In doing so, I aim to explore all the dynamics of abuse. Abusers, as I have portrayed in my thesis, tend to have a deranged sense of reasoning in performing abusive acts and one thing that is important to note is that, more than likely, in their own heads and according to their own reasoning, the behaviour that they act on is very much rational and reasonable. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2022
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Fractured flowers

- Cunningham, Cornelia

Poems caught in dreams

- Jafta, Nthabiseng Rose JahRose

  • Authors: Jafta, Nthabiseng Rose JahRose
  • Date: 2022-10-14
  • Subjects: Creative writing (Higher education) South Africa , South African poetry (English) 21st century
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/406249 , vital:70252
  • Description: My thesis is a collection of Lyrical and Prose Poetry. I am strongly influenced by Marina Tsvetaeva’s observation that “The condition of creation is a condition of dreaming.” As a writer I want to contribute to human knowledge by drawing from a wide literary ancestry, participating in a community of distinct voices and styles to capture and preserve the language of dreams. I fuse inherited knowledge, visions, dreams, my own experiences and what I have discovered through listening to music, reading and my own experiments in exploring poetry in dreams, thoughts and lived experiences. I am inspired by Sindiwe Magona, how she chose to express her spirituality and personal narratives into her work, and Aimé Césaire’s vision “The ground of poetic knowledge, [is] an astonishing mobilization of all human and cosmic forces.” I particularly enjoy intense forms of expression that hold substance and provoke one to elevate in knowledge and in writing. Exploring these combination of forces from these writers affords me an opportunity to write my dreams as reality. Exploring the characters, the different scenes, symbols and colours as poems flashing super/naturally yet leave one with fathomable felt, though sometimes hazy interpretations. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2022
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Portraits

- Fredericks, Gaireyah

An examination of activism and ‘political listening’ during the year of student protest at the University of Cape Town from 9 March 2015 to 9 March 2016

- Mufamadi, Azwihangwisi Eugene

  • Authors: Mufamadi, Azwihangwisi Eugene
  • Date: 2022-10-04
  • Subjects: Student movements South Africa Cape Town , Democracy South Africa , Listening Political aspects , Journalistic ethics , Journalism Political aspects , Communication in social action South Africa Cape Town , University of Cape Town , Cape Times Ltd.
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/327144 , vital:61085 , DOI 10.21504/10962/327144
  • Description: This study sets out to examine democratic participation in South Africa and the role that ‘political listening’ could play in making participation more equitable. It considers protest action on a South African university campus, which at times not only resulted in significant and swift concessions from the university leadership but also sparked national political action which got an equally swift response from the South African government. It considers the social movement, the RhodesMustFall movement (RMF), as one way in which students can organise themselves to get a better hearing from the University of Cape Town (UCT) management in their attempt to make a meaningful contribution to the university’s micro democracy. This study examines whether the interaction between the UCT management and RMF could be considered ‘political listening’, and the possible role of the Cape Times newspaper within this context of participation. Using data gathered through interviews, written communications, observation and newspaper articles, the study shows that in all of the interactions between RMF and the UCT management, both groups were seldom willing to forego their power to engage in genuine listening. Instead, the two parties guessed at what power the other party might have and acted to reduce that power. It is in this context of guessing at and figuring what power the other party has that listening occurs. Furthermore, the study shows that during the RMF protest, the UCT management viewed their responsibility for the institution mainly through the lens of Private Property Law which framed protest as something to be dealt with by restoring law and order. The study also details the role of the Cape Times newspaper in the interactions between RMF and the UCT management and considers if this role could be political listening. The study is exploratory and demonstrates how political listening could work more optimally in real-life instances. , Thesis (PhD) -- Faculty of Humanities, Journalism and Media Studies, 2022
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Computational analysis of known drug resistant mutants of Plasmodium falciparum Dihydrofolate Reductase (PfDHFR) and screening for novel antifolates against the enzyme

- Tata, Rolland Bantar

  • Authors: Tata, Rolland Bantar
  • Date: 2022-04-08
  • Subjects: Uncatalogued
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/234184 , vital:50170
  • Description: Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2022
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Singlet oxygen and optical limiting applications of BODIPYs and other molecular dyes

- May, Aviwe Khanya

  • Authors: May, Aviwe Khanya
  • Date: 2022-04-08
  • Subjects: Dyes and dyeing Chemistry , Phthalocyanines , Photochemotherapy , Active oxygen , Nonlinear optics , Time-dependent density functional theory , Photochemistry
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/294618 , vital:57238 , DOI 10.21504/10962/294620
  • Description: A series of structurally diverse novel and previously synthesized BODIPY core dyes are synthesized and characterized in this thesis. These BODIPYs were synthesized using 2-methylpyrrole, 2-ethylpyrrole, 2,4-dimethylpyrrole and 3-ethyl-2,4-dimethylpyrrole as the starting pyrroles. The combination of different pyrroles with the same aldehyde results in BODIPY core dyes that are structural analogues. These core dyes were used as precursors to synthesise halogenated BODIPYs and novel styrylBODIPY dyes, which were successfully characterized using FT-IR and 1H NMR spectroscopy. The halogenated BODIPY core dyes and the styrylBODIPY dyes were also characterized using MALDI-TOF mass spectrometry. The introduction of heavy atoms on the BODIPY core leads to a red shift of the main spectral. In the presence of styryl groups, the main spectral band red shifts to the far red end of the visible region. As expected, the halogenated BODIPY core dyes also had moderate singlet oxygen quantum yields. These halogenated core dyes were found to be suitable as photosensitizers as all the dyes reduced bacterial viability to below 50% during photodynamic antimicrobial chemotherapy (PACT) studies against Staphylococcus aureus. The structure-property relationships studied demonstrate that the presence of protons rather than methyls at the 1,7-positions or iodines at the 2,6-positions results in more favorable PACT activity. This is likely to be related to the greater ability of the meso-aryl to rotate into the plane of the dipyrromethene ligand and suggests that there should be a stronger focus on dyes of this type in future studies in this field. During nonlinear optical (NLO) studies, all the styrylBODIPYs exhibited favorable reverse saturable absorption (RSA) responses. In the absence of methyl groups at the 1,7-positions, the meso-aryl ring lies closer to the π-system of the BODIPY core, enhancing donor (D)–π–acceptor (A) properties and resulting in slightly enhanced optical limiting (OL) parameters. Additionally, there is no evidence that the introduction of heavy atoms at the 2,6-positions significantly enhances OL properties. In a similar manner, alkyl substituents at these positions also do not significantly enhance OL properties; this was studied for the first time using 15 with ethyl groups at the 2,6-positions. The combination of z-scan data and transient spectroscopy for 16 demonstrated that the main mechanism responsible for the NLO properties of nonhalogenated BODIPY dyes is one-photon absorption from the ground state followed by ESA in the singlet manifold. From the NLO studies of 25, OL parameters of 1,3,5-tristyrylBODIPY dyes were found to be similar in magnitude to properties of distyrylBODIPY dyes, but to have less favorable optical properties for OL applications. The OL properties of scandium phthalocyanines were assessed for the first time, since the Sc(III) ion, unusually for a first row transition metal ion, is known to readily form sandwich complexes. The presence of a Sc(III) ion does not significantly enhance the OL properties of phthalocyanines relative to those of rare earth metal ions that also form complexes of this type. Because BODIPYs and phthalocyanines typically absorb significantly in the visible region, transparent PBC polymer thin films of disilane-bridged compounds with minimal absorption in this region were studied and exhibited an excellent RSA response. These compounds may be useful in the design of OL materials that can protect the human eye. The optimized geometries and spectroscopic properties of selected BODIPYs were studied. As expected, the presence of bromine, iodine, ethyl and styryl groups at different positions of the BODIPY core leads to a narrowing of the HOMO–LUMO band gap, which results in a red-shift of the main spectral band. Partial atomic charges have also been calculated for some of the styrylBODIPY dyes studied for application in OL, and electrostatic potential energy maps were also visualized to better assess how the dipole moment of BODIPY dyes can be modulated since this can affect the OL properties. For all the BODIPYs studied, the electronegativity of the atoms present influences charge distribution on the BODIPY structure. , Thesis (PhD) -- Faculty of Science, Chemistry, 2022
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Visualisation processes in teaching patterns and their generalisation: perceptions and experiences from senior phase mathematics teachers

- Chatima, Simon

  • Authors: Chatima, Simon
  • Date: 2022-04-08
  • Subjects: Visual learning South Africa Eastern Cape , Mathematics Study and teaching (Secondary) South Africa Eastern Cape , Mathematics teachers South Africa Eastern Cape Attitudes , Sequences (Mathematics) Study and teaching (Secondary) South Africa Eastern Cape , Constructivism (Education) South Africa Eastern Cape , Mathematics teachers In-service training South Africa Eastern Cape , VIPRO MATHS Project‎
  • Language: English
  • Type: Master's thesis , text
  • Identifier: http://hdl.handle.net/10962/232936 , vital:50039
  • Description: This study investigated how senior phase mathematics teachers used visualisation approaches to teach patterns and their generalisation as a result of an intervention programme. This project is an integral component of the VIPRO MATHS Project and one of a number of post-graduate research projects which has a particular focus on visualisation processes in mathematics education in the Southern African region. This case study of Senior Phase mathematics teachers in the Chris Hani West District (CHW) in the Eastern Cape Province of South Africa used a social constructivist theory. The study is grounded within an interpretive paradigm explanatory qualitative method design. It surveyed thirty-seven Senior Phase mathematics teachers from schools in the CHW district to get an idea of how teachers teach patterns and their generalisation, prior to an intervention process. After the survey, nine teachers were purposively selected to take part in an intervention programme. They were then observed (teaching) and interviewed to get their perceptions about what factors enable and/or constrain the teaching of patterns and their generalisation when visualisation approaches were used. The data from the survey questionnaire responses, the lesson observations and the interviews were analysed qualitatively. The findings from the survey questionnaire responses revealed that teachers in CHW district value the use of visualisation approaches, although they used visuals to teach patterns in a way that lacked depth, skill and rigor prior to the intervention. Challenges such as difficulty in keeping abreast with the prescribed syllabus, the lack of resources, time constraints, and the limited knowledge of algebra learners have for successfully transferring pictorial representations to symbolic presentations, emerged from the survey data. This necessitated the need for an intervention which focused on the use of a variety of visual strategies and tools to teach patterns and their generalisation effectively. Data from lesson observations showed that all observed participant teachers used visuals to generate image- related questions and created platforms for lively classroom discussions. The teachers used the generated questions to build on learners’ prior knowledge and to promote learner understanding of pattern dynamics that stem from pictorial representations. The data from the interviews revealed that teachers’ perceptions had drastically changed after the intervention. This was because they were now equipped and empowered to effectively make use of visual strategies that enabled them to: build on learners’ prior knowledge, to manipulate visuals for the purpose of prompting learning, develop cognitive perception in learners, cultivate learner innovation and originality and enhance problem solving techniques. This study concludes that the use of visuals enhanced conceptual teaching of patterns and their generalisation in the observed participants. This has the potential to provide mathematics education researchers and curriculum developers with a strong basis to include visualisation processes and strategies into the design of policy documents and to initiate further research efforts. The implications for the teachers are that learners need to be taught ways to create and interpret visual representations in order to understand the dynamics of transferring a pictorial pattern to its resultant symbolic representation expressing pattern regularity. It is also hoped that the results of this study will be utilised by mathematics subject advisers and teacher training institutions to improve the teaching of patterns and their generalisation. , Thesis (MEd) -- Faculty of Education, Education, 2022
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Alcohol use among women attending antenatal care in Buffalo City, Eastern Cape

- Bredenkamp, Petrus Johannes

  • Authors: Bredenkamp, Petrus Johannes
  • Date: 2022-04-07
  • Subjects: Uncatalogued
  • Language: English
  • Type: Master's thesis , text
  • Identifier: http://hdl.handle.net/10962/234358 , vital:50188
  • Description: Alcohol use during pregnancy is known to cause neurodevelopmental disorders in offspring, known as Fetal Alcohol Spectrum Disorders (FASD). High prevalence of FASD has been observed in certain parts South Africa, but many areas of the country remain unstudied, and factors contributing to drinking among pregnant women are poorly understood. This study surveyed 1099 women attending antenatal care at public primary healthcare facilities in the Buffalo City Metropolitan Area in the Eastern Cape. Data was collected using the Alcohol Use Identification Test, a 10-item self-report measure of drinking behaviour in isiXhosa, English, and Afrikaans. Factors associated with alcohol use, risky drinking, binge drinking, and hazardous/harmful drinking were identified using logistic regression. A minority of the sample reported alcohol use (64%). Among those reporting alcohol use, most reported occasional binge drinking (63%) and met criteria for risky drinking (59%) and hazardous/harmful drinking (52%). Living with a regular drinker was significantly associated with alcohol use (OR 1.98, 95% CI 1.51 – 2.58), risky drinking (OR 2.03, 95% CI 1.49 – 2.76), binge drinking (OR 2.21, 95% CI 1.64 – 2.97), and hazardous/harmful drinking (OR 2.0, 95% CI 1.41 – 2.99). However, women who were married/cohabiting were less likely to report alcohol use (OR .71, 95% CI .53 - .95). Experiencing intimate partner violence during the current pregnancy was associated with alcohol use (OR 2.42, 95% CI 1.38 – 4.27) and hazardous/harmful drinking (OR 2.62, 95% CI 1.32 – 5.22). In this study, women who identified as Coloured were more likely to report alcohol use than Women who identified as African (OR 2.74, 95% CI 1.4 – 5.36). These findings simultaneously provide evidence of problematic drinking among pregnant women in a previously understudied area and show that external factors affect women’s drinking behaviour during pregnancy. Interventions aimed at reducing the incidence of FASD should consider alcohol use by pregnant women in the context of their lived experiences. , Thesis (MA) -- Faculty of Humanities, Psychology, 2022
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Alien crosstalk

- Stuart-Watson, Andrew Joseph

Along the river that flowed south

- Mohlomi, Teboho Samson

  • Authors: Mohlomi, Teboho Samson
  • Date: 2022-04-07
  • Subjects: Uncatalogued
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10962/234195 , vital:50171
  • Description: Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2022
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Hiding no scars

- Mhlongo, Sanele

Magnitude

- Seddon, Deborah Ann

  • Authors: Seddon, Deborah Ann
  • Date: 2022-04-07
  • Subjects: Creative writing (Higher education) South Africa , Zimbabwean poetry (English) 21st century , Diaries -- Authorship , Polish literature 21st century History and criticism , English poetry 20th century History and criticism , English literature Irish authors History and criticism , American poetry 21st century History and criticism
  • Language: English
  • Type: Master's thesis , text
  • Identifier: http://hdl.handle.net/10962/234400 , vital:50192
  • Description: My thesis is a collection of lyric, narrative, and prose poetry directed towards two forms of death – physical death and the disavowal of the self. Many poems focus on the death of my mother, and the work required after loss to sort through a family’s life in my Harare childhood home. This associative exploration draws together childhood memories, encounters with physical objects, letters, and songs, as well as with the city and its people. Tadeusz Rózewicz’s Mother Departs has influenced my approach to writing of my mother’s death, particularly how to grant her a voice in the telling. I also draw on the poetry of Harmony Holiday and Pascal Petite, in their attention to the complexities and emotional dangers of the mother-daughter bond. Other poems draw on the work of Adrienne Rich, Audre Lorde, Judy Grahn, Ocean Vuong, and Saeed Jones, in terms of imagining queer life into poetry, the use of the erotic as a means of empowerment, and developing a queer political identity, to examine various aspects of queer love, including the heartaches associated with self-denial. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2022
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Praying mantis

- Kenene, Thobeka

  • Authors: Kenene, Thobeka
  • Date: 2022-04-07
  • Subjects: Creative writing (Higher education) South Africa , Diaries -- Authorship , South African fiction (English) 21st century , South African essays (English) 21st century , Portuguese fiction 20th century History and criticism , Russian fiction 20th century History and criticism , Zimbabwean fiction (English) 20th century History and criticism , American fiction 20th century History and criticism
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/292726 , vital:57010
  • Description: (Prologue) I could only see in black and white as if I had travelled through time. I was the star of the medieval people who waited on me. The city was Johannesburg where strange faces called me a traitor because I was an educated black person. I hid between the skyscrapers and ran into a mirror image of myself as a man. “I write this book,” he said to his readers, “To invoke a yearning in our youth to awaken from slumber. To set examples for them to desist from characters like Velesazi and Nongendi, and imitate Nomsa and Themba. And also, to contribute to Xhosa literature.” He signed off by calling himself our servant. These are the words from the note my great-grandfather left me. We walked together across a barren field and past a graveyard. I was feeling tired and lost; I wanted to get home as fast as possible. We quickened our step and entered a church site. Inside the church were all my close relatives. I saw myself on stage looking down at them, and when I opened my mouth to sing, they began laughing at me. I imagined him in his 1917 suit, as a writer, penning down his first novel that is dedicated to his mother. His round cheeks enveloped in a haze of candle light. He visited my dream in 2012 and in the dream he asked me, “Do you see?” I said, “Yes, I see.” My great-grandfather hummed a song from his belly. I inhaled deeply into my belly and then exhaled a sound. Together we hummed this song that made everyone fall silent and listen. In the dream I could feel my lungs expanding and deflating along to the rhythm of the song. As my great-grandfather and I sang it, the night lamps shone brighter. I had become my great-grandfather, wearing his suit and black leather shoes. His friends were my friends. They turned and asked me what my clan name was. When I told them, they whispered something among themselves. One of them said to me, “Unogcwabevu.” I saw a white unknown woman who was afraid of me. I told her it is going to be okay, and that I would not harm her. But the colour of my skin frightened her. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2022
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Sexual socialisation: young adult women storying how sexual activities were discussed in South African cultural contexts

- Ludidi, Zizipho

  • Authors: Ludidi, Zizipho
  • Date: 2022-04-07
  • Subjects: Socialization South Africa , Sex Social aspects South Africa , Young women Socialization South Africa , Young women Sexual behavior South Africa , Culture , Memory , Narrative inquiry (Research method)
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/292737 , vital:57011
  • Description: Epidemics such as HIV/AIDS, unplanned pregnancy, gender-based violence and homophobia, in South Africa, have focused research on how young people learn about sex. This research has often focused on young girls from risk-saturated areas, and specific agents of socialisation, where they might learn about sex, such as parents, life orientation at schools, peers, media, and traditional cultural approaches. Using a narrative theoretical framework, through memory work, this study explored how black young adult women friends – who were university students – experienced forms of sexual socialisation, through various communication in South African cultural contexts. Findings from the thematic narrative analysis that was conducted demonstrated that sexual socialisation is a complex life-long process. This takes place through a collision of contradictory messages, from different agents of socialisation, in different cultural contexts. Themes were identified and organised to tell an overall sexual socialisation story that progressed through time, moving from a stage of perceived innocent oblivion, mixed messages in primary and high school, “liberal” university stories and the current stage of reauthoring stories. , Thesis (MA) -- Faculty of Humanities, Psychology, 2022
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Skipping stones

- Le Roux, Jade-Eden

  • Authors: Le Roux, Jade-Eden
  • Date: 2022-04-07
  • Subjects: Creative writing (Higher education) South Africa , South African fiction (English) 21st century , Suicide in literature
  • Language: English
  • Type: Master's thesis , text
  • Identifier: http://hdl.handle.net/10962/234389 , vital:50191
  • Description: My thesis takes the form of a novella exploring suicide and the unanswered questions it leaves. The main protagonist is a young girl who struggles to come to terms with her best friend’s suicide. The work is situated in contemporary South Africa, where inequality and depression is rife, especially among young people, and social media too often provides a smokescreen to conceal emotions. My writing is motivated by my desire to explore the human condition and the world around me, through my own subjective lens of experience. By working between fact and fiction I seek to trouble conventional narratives attached to suicide and highlight the subjectivity of truth. I am influenced by Lydia Davis's ability to write obliquely about loss, and her light-handed approach to emotionally charged topics; Susan Steinberg's dark motifs, vivid imagery, and her fragmented narrative that captures the characters’ responses to trauma and interrogates the notion of truth; Lidia Yuknavitch's cinematic imagery and immediacy of tone and compact storytelling; and Kate Zambreno's poetic prose that lends itself to clear societal commentary. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2022
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The mountain’s calling

- Mabeba, Motlatjo Ahsley

Comparison of a novel HPLC method and conventional protein assays for the quantitation of insulin aspart in Novorapid®

- Dickson, Courtney Rae

  • Authors: Dickson, Courtney Rae
  • Date: 2022-04-06
  • Subjects: Uncatalogued
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10962/290704 , vital:56776
  • Description: Thesis (MSc) -- Faculty of Pharmacy, Pharmacy, 2022
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Fabrication and characterization of ciprofloxacin loaded niosomes for transtympanic delivery

- Mhlanga, Asavela

  • Authors: Mhlanga, Asavela
  • Date: 2022-04-06
  • Subjects: Drug delivery systems , Liposomes , Ciprofloxacin , Quinolone antibacterial agents , Drug carriers (Pharmacy) , Drug stability , Lamellarity‎ , Niosomes‎
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/290715 , vital:56777
  • Description: Ciprofloxacin (CPH) is a broad-spectrum antibiotic used to treat bone, joint, and skin infections. It is commercially available as an extended-release tablet and as a cream dosage form. CPH is a bactericidal active pharmaceutical ingredient (API) of the fluoroquinolone drug class. It inhibits deoxyribonucleic acid (DNA) replication by inhibiting bacterial DNA topoisomerase and DNA gyrase enzymes. Common adverse effects include nausea, vomiting, unusual fatigue, pale skin, and may increase the risk of tendinitis, which could be a major concern. CPH is, according to the Biopharmaceutics Classification System (BCS), classified as a BCS class IV drug exhibiting low oral bioavailability, low solubility, and intestinal permeability. CPH was chosen as a good candidate for the study because of its stability in solutions, its low molecular weight (331.4 g/mol), and its moderate lipophilicity (log P = 0.28) [16]. The use of conventional ear drops in the ear is effective, avoids hepatic first metabolism and extensive protein binding and may reduce adverse effects as a low dose may be used to achieve a therapeutic effect. However, conventional ear drops and oral antibiotics have a long onset of action and have to be taken/applied in short intervals. For convenience and assurance of a long residence time in the ear, CPH may be delivered by using a niosomal formulation, a liquid at room temperature, to allow administration into the ear without the need to constantly apply the ear drops for long periods of time. A simple, rapid, precise, accurate, reproducible, and specific reversed-phase high-performance liquid chromatography (RP-HPLC) method using ultraviolet (UV) detection for the quantitation of CPH was developed and optimized using a central composite design (CCD). The method was validated using International Conference on Harmonisation (ICH) guidelines and was found to be linear, precise, accurate, and specific for the analysis of CPH. Since the method is specific, it was used to quantify CPH in commercial and experimental formulations and monitor CPH released during in-vitro release testing. The compatibility of CPH and potential excipients was investigated during preformulation studies using Fourier transform infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC) to identify and select suitable excipients for use during formulation development activities. No apparent interactions were evident between CPH, and the excipients tested. The probe sonication method was used to manufacture CPH loaded niosomes using different surfactants/surfactant combinations, and a combination of Tween® 80: sodium lauryl sulfate (SLS) was found to be the best composition in terms of both entrapment efficiency and Zeta potential. The limits for the independent input variables used for the manufacture included amplitude, sonication time, and amount of cholesterol were determined. Design of experiments (DOE) was used to design the study. The input variables investigated included amplitude, amount of cholesterol, and sonication time. The output or responses monitored included Zeta potential, vesicle size, polydispersity index (PDI), and entrapment efficiency. Non-ionic surfactant systems are predominantly stabilized by steric stabilization, and there is only a minor electrostatic element from adsorbed hydroxyl ions. With the inclusion of SLS it is to be expected that Zeta potential will be a contributing factor. DOE using Box-Behnken design (BBD) and response surface methodology (RSM) in addition to Artificial Neural Networks (ANN) were used for the optimization of the formulation. The optimized formulation had a composition of 1 g cholesterol, 1 g of Tween® 80, 1 g of SLS and was prepared at an amplitude of 11.294 % with a sonication time of 3.304 minutes. The formulation exhibited zero-order release kinetics and had an average pH of 7.45. The formulation was stored at 4 ℃ and 25 ℃ and was assessed for vesicle size, entrapment efficiency, Zeta potential, colour, lamellarity, and PDI every 7 days for 4 weeks. The lead formulation stored at 4 ℃ was more stable than the formulation at 25 ℃ in terms of entrapment efficiency, PDI and vesicle size during the 4-week period. CPH loaded niosomes for transtympanic delivery in the treatment of otitis media were developed and optimized. The technology exhibits sustained release of CPH and has the potential for further development and optimization. , Thesis (MSc) -- Faculty of Pharmacy, Pharmacy, 2022
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