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Exploring the reception of global health campaigns at a local level: a study of the WHO #SafeHands handwashing social media campaign for the Coronavirus (COVID-19) pandemic on Twitter.
No full textMasters Degree. University of KwaZulu-Natal, Durban.This study explores the efficacy of the universal WHO #Safehands Handwashing campaign at a localised level, specifically for students at the University of KwaZulu-Natal (UKZN) in South Africa. It is essential to develop a greater understanding of the reception and effectiveness of global health campaigns in the context where they are received to improve future campaigns' success. This study also explores participatory platforms for health communication, such as social media platforms, to determine if they have a more significant impact on behaviour change. This study is helpful in assessing whether these platforms should be used more often in the future to achieve a greater impact on health communication campaigns. A further objective of this study is to better understand the affordances and limitations of health communication campaigns on Twitter (now X), as Twitter was the main platform utilised to distribute the WHO #SafeHands Handwashing campaign. This study is beneficial in guiding future campaigns that plan to utilise Twitter as an example of social media to disseminate health communication campaigns, particularly pandemic campaigns, as more effective campaigns can save lives. Within the study, a qualitative research approach was performed in the form of online focus groups conducted via Zoom. The sample included registered UKZN students based in KwaZulu-Natal who were either in a rural or urban area during the initial COVID-19 lockdown period. The data analysis technique performed was the six-phase reflexive thematic analysis process to identify emerging themes and differentiate the three potential readings of the campaign from Stuart Hall’s Reception Analysis. Reception Analysis and Participatory Culture were the theoretical guides for this study. The reception of the campaign was positive overall, and participants felt better equipped to wash their hands effectively after seeing the campaign. The challenge of recreating videos within the campaign, which encouraged participants to actively participate in the campaign, however, was not received as positively. This is largely due to inadequate living conditions, whereby some participants did not have the same facilities or basic amenities,such asrunning water. The study discovered that vast contrasts in the living conditions of some of the local 4 participants had impacted the effectiveness of the WHO #Safehands Handwashing campaign for these participants. The impact of this research highlights the need for global health authorities to work closely with local health authorities to ensure that unique regional circumstances and cultural differences are considered when designing campaigns. For global health campaigns to be more impactful and relatable, they may need to be adapted within different regions. By taking this into consideration, global campaigns may be more successful and ultimately save lives
Carnivore ecology and diet assessment using DNA-based approaches: the elusive black-footed cat (Felis nigripes) as a case study.
No full textDoctoral Degree. University of KwaZulu-Natal, Pietermaritzburg.Information obtained from the assessment of diet has been used to reconstruct food webs of elusive and shy predators that are difficult to observe in their natural habitats. The information from these studies has been crucial in developing conservation strategies. Predator-prey dynamics in particular, can also be used as a proxy of ecosystem health. Traditional approaches for diet analysis often involve direct observation or morphological identification of prey remains from scat. These approaches can be challenging for smaller predators that are difficult to track, and are generalist, opportunistic or scavenging carnivores. This is because traditional methods are not well adapted to analyze and identify such a wide variety of prey species, making them liable to bias and inaccuracy. DNA-based methods for the identification of diet from scats have been shown to provide better resolution, accuracy and consistency when compared to all other methods. Species identification of prey consumed can be achieved using DNA barcoding; identification of species through the amplification of specific genetic markers linked to taxonomically identified species. DNA metabarcoding is a recent technological advancement which allows for identification of multiple species from a single sample using high-throughput sequencing (HTS). Using the shy and elusive black-footed cat (Felis nigripes, Burchell 1824) as a case study, in this dissertation I aimed to determine if DNA-based methods could be used to provide important population-level information (number of individuals in population, relatedness of individuals, dietary components, and parasite load). The first data chapter (Chapter 2) aimed to provide an in-depth review of the state of DNA reference libraries for small South African mammals. Small mammals constitute a large portion of small and medium carnivore diet. As such, the abundance of DNA reference libraries for small mammals gives a good indication if DNA metabarcoding studies are feasible. Analysis of DNA
records revealed that the majority of small mammals are represented by at least one of the five mitochondrial genes. This study supports the use of multiple gene regions when performing scat metabarcoding particularly when wanting to determine the small mammal component of the diet. Chapter 3 tested in silico if published metabarcoding primers for 12S rRNA, 16S rRNA, COI and cyt b could reliably delimit common prey items eaten by black-footed cats. Successful species delimitation using metabarcoding rests on the presence of a “DNA barcode gap”. This gap is the difference between intraspecific and interspecific genetic distances within a group of organisms. Eight metabarcoding primer pairs were chosen from the literature. Using an alignment of DNA sequences from South African small mammals, each amplicon produced by the primer pairs was tested to determine if species level identification could be made. An optimal set of primers were developed for use in black-footed cat (and other small and medium carnivores) diet analyses. Chapter 4 assessed if microsatellites previously designed for use in domestic cat (Felis silvestris catus) could be successfully amplified and used to identify individual black-footed cats from scats. All nine microsatellite loci used in this study were amplified successfully and were polymorphic. The loci were found to have sufficient discriminatory power to distinguish individuals and identify clones and could therefore be used in parentage assignments. Chapter 5 aimed at identification of prey items of black-footed cats in the Benfontein Nature Reserve, Kimberley, South Africa using DNA metabarcoding. Of the four DNA regions selected for high-throughput sequencing, the cyt b region did not sequence well and was therefore excluded from the study. The result from this study were compared to a previous study conducted which was based on direct observations of black-footed cat feeding. Unsurprisingly, our DNA data supported previous studies which showed that the diet of black-footed cat consists mainly of rodents. Importantly, the DNA metabarcoding results identify some prey items that have not been recorded in black-footed cat diet previously highlighting the sensitivity of the DNA-based method. For example larger prey items such as antelope were also identified suggesting that the cats may also opportunistically scavenge. Chapter 6 assessed the presence of parasites found in black-footed cat wild populations. Five pathogens known to be of veterinary importance in domestic cats were found in the black-footed cat scats. These pathogens had previously not been documented in wild African felids, but are well documented in other taxa. These results add to the growing knowledge of diseases that could possibly contribute to the declining populations of black-footed cats in South Africa. In conclusion, DNA based methods have been shown to improved species resolution when compared to traditional methods of diet assessments. More so when coupled with highthroughput sequencing technologies. The results of this study show that DNA metabarcoding can be applied successfully to study the diet of South Africa carnivores. The results also indicate that DNA metabarcoding can be used in identification of species that are endemic to southern Africa
Livestock identification and tracking system for controlling livestock theft: case study of South Africa.
No full textDoctoral Degree. University of KwaZulu-Natal, Durban.This thesis explores livestock theft problem within the South Africa context, focusing on cattle, sheep, and goats, and evaluates the potential of Information and Communications Technologies (ICTs) to address this critical problem. Conventional identification and tracking methods are currently ineffective, prompting the need for ICT based solutions. Despite calls for ICT intervention, no comprehensive conceptual model exists for South Africa. This study aims to fill this gap by proposing an ICT-based national livestock identification and tracking system to control livestock theft in South Africa. Utilizing Actor-Network Theory and a qualitative approach, the research includes interviews and questionnaires with stakeholders such as farmers, police, and stock theft forums. The study also integrates secondary data and literature, supported by a Scoping Review, snowball strategy, PRISMA method, and CASP framework. Data analysis employed thematic and content analysis techniques. Findings reveal that livestock theft networks are well-organized, highlighting the need of a unified national ICT based solution to combat livestock theft. The study identifies several potential ICT tools such as mobile phones, biometric technology, radio and TV broadcasting, camera traps, cloud computing, and drones as viable solutions. The proposed conceptual model of a national livestock identification and tracking system features two modules: retinal pattern-based biometric identification and three tracking methods. A Design Science Research Methodology (DSRM) framework was used to present the conceptual model for the proposed system. Recommendations emphasize the need for collaboration among stakeholders, including the Department of Agriculture, South African Police Service, and State Information Technology Agency. Limitations include a focus on the top ten livestock theft-hotspots and reliance on secondary data, with suggestions for future research to involve direct data collection from additional informants and explore how perpetrators use ICTs. The study contributes empirical insights and presents a practical model for controlling livestock theft through ICTs, along with a business case for its implementation. Future research should address the political implications and technical details of the ICT solution, as the current study does not cover the implementation process
Improvement of maize (Zea mays L.) for heat stress tolerance in Zimbabwe to enhance climate resilience in new genotypes = Ukuthuthuka koMbila (Zea mays L.) ngokubekezelela ingcindezi yokushisa eZimbabwe ukukhulisa ukubekezela kwesimo sezulu kulibofuzo lokuphilayo.
No full textDoctoral Degree. University of KwaZulu-Natal, Pietermaritzburg.Maize (Zea mays L.) is an important crop for food security globally. Rising temperatures due to climate change have significantly affected production and productivity of maize in sub Saharan Africa (SSA). Global warming is predicted to increase the frequency, duration, and intensity of heat stress, but the region's ability to adapt to these changes is limited. Given the significant maize yield losses reported due to heat stress, the use of high yielding heat tolerant maize varieties offers a sustainable solution to these challenges. In Zimbabwe and SSA at large, breeding maize for heat stress tolerance is at infancy stage. Therefore, the objectives of this study were to i) determine the genetic potential of exotic heat stress tolerant maize donor lines (HSTDLs) obtained from CIMMYT-India and CIMMYT-Zimbabwe elite lines for potential use in sub-tropical breeding programs, ii) assess the genetic diversity and genetic purity of heat donor lines and elite CIMMYT-Zimbabwe lines using single nucleotide polymorphism (SNP) markers, and iii) determine the performance and yield stability of early maturing commercial hybrids currently on the market in Zimbabwe under heat stress and random drought and heat stress conditions. In the first study, 14 HSTDLs from CIMMYT-India were crossed with 15 locally adapted elite lines from CIMMYT-Zimbabwe using the North Carolina Design II mating scheme. The successful 175 crosses were evaluated together with five commercial hybrids at two locations in the lowveld area of Zimbabwe during the 2020 winter season under managed heat stress and optimal conditions. The parental line trial was planted adjacent the hybrid trial at each location to determine the per se performance of the heat donor lines under heat and optimal conditions. The sentence was restructured and its now reading ― The design II analysis revealed significant (p <0.01) general combining ability (GCA) and specific combining ability (SCA) effects for GYD under heat stress (HTS), optimal conditions (OC), and across locations an indication that GYD is controlled by both additive and non-additive gene action. Three HTSDLs (CAL14138, CAL152, and CAL1440) exhibited significant positive GCA effects for GYD under HTS conditions. The crosses DJ265-15 × VL1018816 and DJ267-9 × CAL1440 revealed positive significant SCA for GYD under HTS. The donor lines (HTSDLs) CAL14138, CAL152 and VL109126 exhibited superior per se performance under HTS, OC and across environments.
Thirty five inbred lines were genotyped to assess their genetic diversity, relatedness and purity using 94 single-nucleotide polymorphism (SNP) markers. The identity-by-state (IBS) genetic distance matrix revealed pairwise genetic distance among the inbred lines ranging from 0.04 to 0.64. The widest genetic distance was between inbred line pairs: CZL1112c and CZL16018; CAL14135 and ZL132077; and CZL15153 and CZL16018. The shortest genetic distance was between inbred lines CAL152 and CAL14138, CAL14138 and VL109126; and ZL132077 and DJ611-1. The neighbor-joining algorithm grouped inbred lines into three different main clusters. Some heat tolerant donor lines clustered together with local lines, while the other cluster consisted of either CIMMYT-Zimbabwe or CIMMYT- India lines. Majority (85.78%) of lines assessed were genetically pure with less than 5% heterozygosity. About 54.28% of the inbred lines evaluated exhibited 100% genetic purity.
In the third study, 20 early maturing commercial hybrids and 5 experimental hybrids were evaluated across six locations during the 2020/21-2021/22 seasons for adaptability and stability under heat stress, random drought and heat stress conditions. The genotype main effect plus genotype x environment interaction (GGE) biplot showed that commercial hybrids G3 (4.79 t ha- 1), G20 (3.99 t ha-1) and G22 (4.09 t ha-1) were the most adapted under HTS condition while experimental hybrid, G4 (4.31 t ha-1), was the most adapted under HTS conditions. Under random drought and heat stress (RDHS) conditions, the most adapted commercial hybrids were G12 (4.66t ha-1), G14 (4.39 t ha-1), G15 (4.02 t ha-1), G13 (4.17 t ha-1), G21 (3.76 t ha-1) and G25 (3.50 t ha-1). The ‗ranking‘ GGE biplot identified commercial hybrids G16 (4.94 t ha-1) and G3 (4.79 t ha-1)as high yielding and stable across stress and non-stress conditions. The experimental hybrids G6(4.77 t ha-1) and G7 (4.67 t ha-1) were stable across environments. The experimental genotype, G8 (5.47 t ha-1), was overally, the highest performing but was unstable. The exotic lines that exibited significant positive GCA can be exploited for introgression of heat tolerant genes into local maize populations in breeding for heat stress tolerance. The availability of genetic diversity and the relationship observed among the HSTDLs and the local lines shows that there are valuable heat tolerant inbred lines within CIMMYT- Zimbabwe programme that could be used in heat stress tolerance breeding in SSA. Generally the study shows the potential of breeding for heat stress tolerance in SSA.
Iqoqa.
Ukukhuphuka kwamazinga okushisa ngenxa yokuguquka kwesimo sezulu sekube nomthelela omkhulu emkhiqizweni wombila e-Afrikha engezansi kweSahara, yize ukukhiqiza okubekezelela ingcindezi yokushisa kusasesigabeni esiphansi kakhulu. Lolu cwaningo lwenziwa ukuhlola i) ufuzo olungaba khona lohlobo lombila olubekezelela ingcindezi yokushisa okungajwayelekile (HSTDLs) oluphuma ezinhlotsheni i-CIMMYT-India kanye nezinhlobo zohlobo oluphezulu ze-CIMMYT-Zimbabwe ezingasetshenziswa ezinhlelweni zokukhiqiza ezingezansi kweSahara, ii) ukwehluka kofuzo kanye nobumsulwa kwalezizinhlobo kusetshenziswa izikali zezakhi ezahlukene zokuqalela, kanye iii) ukusebenza kwengxube ethengisekayo esheshe ivuthwe ekhona eZimbabwe ngaphansi kwengcindezi yokushisa kanye nezimo zesomiso ezivele zibe khona nje kanye nengcindezi yokushisa. Kulolu cwaningo, ama-HSTDL ayi-14 aphanjaniswa nezinhlobo ezilungisiwe zangaphakathi eziyi-15 ku-CIMMYT-Zimbabwe ngokusebenzisa uHlaka lweNorth Varoline II lohlelo lokuhlanganisa. Ukuphambanisa okunempumelelo kwahlolwa ezindaweni ezimbili eZimbabwe ngesikhathi sasebusika sika-2020 ngaphansi kwezimo ezenganyelwe zengcindezi yokushisa kanye nezilungile. Isivivinyo sohlobo lomzali lwatshalwa eduze nesivivingo esingxube endaweni ngayinye ukuthola ukusebenza kwayo ngayinye kohlobo ngalunye olusetshenzisiwe. Ukuhlaziya koHlaka II kwaveza (p < 0.01) okukhulu okwejwayelekile kanye nemithelela yokukwazi ukuhlanganisa ethile ye-GYD kuzo zonke izindawo, okukhomba ukuthi i-GYD inomthelela ngomsebenzi wofuzo olwengeziwe nolungangeziwe. Ocwanigweni lwesibili, ezikhiqizwe ngaphakathi ezingama-35 zazinolibofuzo lokuphilayo kusetshenziswa izikali ze-94 SNP ukuhlola ukwehluka kofuzo lwazo, ukuhlobana kanye nobumsulwa. Isihlonzandawo sobude bendawo yofuzo esikhombeka ngokwesimo saveza ubude bendawo obuhlobene nokuqhathanisekayo phakathi kwezinhlobo ezihlobeke kusuka ku-0.04 kuya ku-0.64. ukusondela kwezibalo zezinombolo kanye nezimpawu ezihlanganisayo kwaqoqela ndawonye izinhlobo ngamaqoqo amathathu ehlukene nezinye izinhlobo ezingajwayelekile kanye nezangaphakathi zaqoqelwa ndawonye bese amanye amaqoqo ayenezinhlobo ezingejwayelekile kanye nezinhlobo zangaphakathi. Izinhlobo ezingangama-85.78% ezahlolwa zazinofuzo olumsulwa. Ocwaningweni lwesithathu, izingxube ezithengisekayo ezisheshe zivuthwe ezingama-20 emakethe eZimbabwe kanye nezingxube zokulinga ezi-5 zahlolwa kuzo zonke izindawo zangaphakathi eziyisithupha ngezikhathi zika-2020/21-2021/22 ukuvumelana kanye nokuma ngaphansi kokushisa, izimo zesomiso esifika nje kanye nengcindezi yokushisa. Ukuhlaziya ngegrafu eveza ukusabalala kwamaverabuli amabili e-GGE kwaveza ukuthi ingxube enxantathu yokudayisekayo kanye nengxube yolingo yavumela nengcindezi yokushisa ngesikhathi ingxube yokuthengisekayo eyisithupha yavumelana ngaphansi kwezimo zesomiso ezifika nje kanye nengcindezi yokushisa. Igrafu yokukala eveza ukusabalala kwamaverabuli amabili yaveza izingxube ezithengisekayo i-G16 kanye ne- G3 njengezikhiqiza kakhulu futhi ezisimelele kuzo zonke izimo
Female principals’ leadership experiences in rural schools in KwaZulu-Natal = Amava obuholi bothishanhloko besifazane ezikoleni zasemakhaya KwaZulu-Natali.
No full textDoctoral Degree. University of KwaZulu-Natal, Pietermaritzburg.Women face multiple challenges in accessing and participating in educational leadership, and this remains a problem and compelling issue for research. This study aimed to explore female principals’ leadership experiences in six selected public primary rural schools in the KwaZulu-Natal Province in South Africa. To understand women's leadership experiences, the study examined their biographies, early learning, and school experiences as leaders. An intersectional lens was employed to understand women’s multiple challenges encountered in educational leadership based on an interlocking system that shapes the interpersonal, organisational, and structural aspects of their experiences. This reflects Collin’s (2000) assertion that cultural, structural, and interpersonal domains are intertwined, collectively shaping gender dynamics.A qualitative approach with a narrative inquiry design was applied, and six female principals were purposively selected from rural schools. The data was collated using semi-structured interviews, a focus group discussion, and photographs and analysed using content analysis. The findings reveal that women experience multiple challenges in the form of gender stereotypes, discrimination, prejudices, bias, rejection, and infantilisation. Women’s biography, early learning, and school experiences shape and influence how women lead. The study concludes that the nature of women’s leadership experiences is linked to multiple factors, situations, and events; thus, it is personal and complex, and rural women must overcome and surpass the challenges through resilience and supportive environments. The study has implications for leadership structures, women leaders, and policymakers.
Iqoqa.
Abesifazane babhekene nezingqinamba eziningana ekungeneni nasekuzibandakanyeni ebuholini kwezemfundo, futhi lokhu kuseyinkinga futhi indaba esadinga ukucwaningwa. Lolu cwaningo luhlose ukuphenya izimo zobuholi bothishanhloko besifazane ezikoleni ezikhethiwe eziyisithupha zamabanga aphans, ezisemakhaya esiFundazweni saKwaZulu-Natali eNingizimu Afrika. Ukuqonda izimo zobuholi babesifazane, ucwaningo luphenye imvelaphi yabo, ukufunda kwabo kwangaphambilini, kanye nezimo zezikole njengabaholi. Ukubuka ngeso lezingxenye ezixhumanayo kwasetshenziswa ukuqonda izingqinamba eziningana abesifazane abahlangabezana nazo ebuholini bezemfundo ngokwendlela yokuvaleleka ngaphakathi nokuyiyona ebumba ukusebenzisana phakathi kwabantu, ukusebenza, kanye nokuhleleka kwezimo zabo zokusebenza. Lokhu kuveza ukuqinisekisa kukaCollin (2000) ukuthi izinhlaka zamasiko, zokuhleleka kanye nokusebenzisana phakathi kwabantu akwehlukaniseki, ngokuhlangana kwakho konke okubaliwe lokho kubumba ukwehlukahlukana kobulili. Indlelakwenza yobunjalo botho kanye nohlelo lwendlela elandisayo kwasetshenziswa, futhi abaphathizikole besifazane abayisithupha bakhethwa ngenhloso ezikoleni ezisemakhaya. Imininingo yaqoqwa kusetshenziswa izingxoxo ezisakuhlelela, izingxoxo zamaqoqo, kanye nemifanekiso kwahlaziywa ngokusebenzisa uhlaziyongqikithi. Imiphumela iveza ukuthi abesifazane babhekana nezingqinamba eziningana ngendlela yokucwaswa ngokobulili, ukubukelwa phansi, ukubandlululwa, ukuphathwa ngendlela engafani neyobunye ubulili, ukunganakwa, kanye nokuphathiswa okwezingane. Imvelaphi yabesifazane, ukufunda kwabo kwangaphambili, kanye nezimo zesikole kubumba futhi kube nomthelela ekutheni abesifazane bahola kanjani. Ucwaningo luphetha ngokuthi umumo wezimo zobuholi babesifazane uhlobene nezinkomba ezahlukene, izimo kanye nezehlakalo; ngaleyo ndlela, kungokomuntu ngamunye futhi kuyadida, kanti futhi abesifazane basemakhaya kumele babhekane futhi badlubulundele ezingqinambeni ngokubekezela kanye nezizinda ezesekelayo. Ucwaningo lunemithelela yezinhlelo zobuholi, abaholi besifazane kanye nabaqambi benqubomigomo
Derivatised phenanthroline transition metal chelates : targeted chemotherapeutic agents = I-Derivatised phenanthroline transition metal chelates: i-targeted chemotherapeutic agents
No full textDoctoral Degree. University of KwaZulu-Natal, Pietermaritzburg.The derivatisation of 1,10-phenanthroline at the 2-position afforded two classes of compounds with two different bridging groups in this study. The first group comprised two amide-bridged tetradentate N4-donor ligands and were chelated to copper(II), nickel(II) and palladium(II). The ligand chelation occurred with concomitant deprotonation of the amide N-H, resulting in a monoanionic ligand and monocationic complexes when coordinated to the divalent metal ions. The ligands N-(quinolin-8-yl)-1,10-phenanthroline-2-carboxamide, HL1, and N-(pyridin-2-ylmethyl)-1,10-phenanthroline-2-carboxamide, HL2, were characterised by NMR, IR and UV/vis spectroscopy as well as mass spectrometry. The second class of compounds were imine-bridged copper(II) chelates. These chelates were synthesised via a templating condensation reaction between various salicylaldehyde derivates and 1,10-phenanthrolin-2-ylmethanaminium chloride, yielding eight additional copper(II) chelates. The metal chelates were characterised by IR, UV/vis and EPR spectroscopy, and mass spectrometry. HL1, [Cu(L4)(NO3)] and [Cu(L7)](NO3) were further studied by X-ray diffraction. The copper(II) chelates exhibit two different solid-state structures with the nitrate counter ion coordinated to the metal centre in [Cu(L4)(NO3)], but in the outer coordination sphere for [Cu(L7)](NO3). The paramagnetic copper(II) chelates were studied with EPR spectroscopy, which confirmed the square planar coordination geometries of these chelates in solution. The metal chelates were designed to be chemotherapeutic agents, exerting their cytotoxicity through DNA intercalation and, for the copper(II) chelates, DNA cleavage through the catalytic production of ROS. The ability of the copper(II) chelates to catalyse the production of hydroxyl radical in situ in the presence of ascorbic acid and hydrogen peroxide was studied via a hydroxyl radical assay using Rhodamine B as an analogue for the aromatic DNA bases. Competitive binding studies determined the affinity of the metal chelates towards ct-DNA, [Cu(L1)](PF6) has the highest binding constant: 5.91 × 106 M-1. DFT calculations were performed on the ligands and metal chelates to determine the geometry-optimised structures, vibrational frequencies, 1H and 13C NMR chemical shifts and electronic transitions. The B3LYP/6-311G (d,p) level of theory was used for the ligands, copper(II) and nickel(II) chelates and the B3LYP/LanL2DZ level of theory for the palladium(II) chelates. The TD-DFT method was used for the energy calculations. The experimental and calculated results were compared where possible, and a reasonable correlation was found. The cytotoxicity of five amide-based chelates was evaluated against four human cancer cell lines, namely A549, TK-10, HT29 and U251, using an MTT assay. The screened chelates exhibited favourable anticancer activity with the mean IC50 values against the four cancer cell lines ranging from ca. 12 to 35 μM. Importantly, it was found that the combination of the copper(II) ion and the ligand was essential for enhanced cytotoxicity. The complex [Cu(L1)](PF6) was identified as the lead drug candidate based on the high DNA affinity and cytotoxicity. This compound was most cytotoxic towards the glioblastoma cell line U251 with an IC50 value of 7.59 μM. The imine-based chelates were screened against three human cancer cell lines: MDA-MB, HELA, and SHSY5Y, and a healthy human cell line, HEK293. The selectivity index of these chelates for neoplastic versus the healthy cell line was calculated. The imine-based chelates showed a high selectivity towards the triple-negative breast cancer MDA-MB, an order of magnitude more toxic to the tumour cell than the healthy one. This selectivity index is significantly improved over that of cisplatin. A gel mobility shift assay investigated the interactions between the copper(II) chelates and plasmid DNA. The in vivo biodistribution of [Cu(L1)](PF6) was determined using the copper-64 radiolabelled analogue of [Cu(L1)]Cl and microPET-CT scanning. The initial biodistribution studies suggested that the complex has good serum stability and showed that there was no significant accumulation in any organs. The subsequent study involved a xenograft model using the A549 cell line and showed significant uptake and retention of the complex in the tumour. The cytotoxicity of the chelate when synthesised with the non-radioactive isotopes of copper and the uptake of the radiolabelled equivalent in a tumour model suggest that this complex could have application as a “theranostic agent”.
Iqoqa.
Ukukhishwa kwe-1,10-phenanthroline endaweni ye-2 kunikeze amakilasi amabili enhlanganisela namaqembu amabili ahlukene ukuhlanganisa kulolu cwaningo. Iqembu lokuqala lalihlanganisa ama-amide-bridged tetradentate N4-donor ligands futhi ayenziwe ngethusi (II), nickel (II) kanye ne-palladium (II). I-ligand chelation yenzeke ngokuchithwa okuhambisanayo kwe-amide N-H, okuholela ku-monoanionic ligand kanye ne-monocationic complexes lapho ixhunywe kuma-ion ensimbi e-divalent. Ama-ligands N-(quinolin-8-yl)-1,10-phenanthroline-2-carboxamide, HL1, kanye ne-N-(pyridin-2-ylmethyl) -1,10-phenanthroline-2-carboxamide, HL2, abenophawu lwe-NMR, IR kanye ne-UV/vis spectroscopy kanye ne-mass spectrometry. Ikilasi lesibili lama-compounds bekungama-imine-bridged copper (II) chelates. Lawa ma-chelates ahlanganiswa ngokusabela kokujiya kwesifanekiso phakathi kokuphuma kwe-salicylaldehyde okuhlukahlukene kanye ne-1,10-phenanthrolin-2-ylmethanaminium chloride, ekhiqiza ama-chelate ethusi ayisishiyagalombili (II). Ama-chelates ensimbi abonakala nge-IR, UV/vis kanye ne-EPR spectroscopy, kanye ne-mass spectrometry. I-HL1, [Cu(L4) (NO3)] kanye ne-[Cu(L7)] (NO3) zaphinde zacwaningwa nge-X-ray diffraction. Ama-chelates ethusi (II) abonisa izakhiwo ezimbili ezihlukene zesimo esiqinile ezine-ion yekhawunta ye-nitrate exhunywe esikhungweni sensimbi ku-[Cu(L4) (NO3)]], kodwa kwi-outer coordination sphere ye-[Cu(L7)] (NO3). Ama-chelates e-paramagnetic copper (II) ahlolisiswa nge-EPR spectroscopy, eqinisekisa i-square planar coordination geometries yalawa ma-chelates esixazululweni.
Ama-chelates ensimbi ayeklanyelwe ukuba abe ama-chemotherapeutic agents, asebenzisa i-cytotoxicity yawo ngokusebenzisa i-DNA intercalation futhi, kuma-chelates ethusi (II), i-DNA cleavage ngokukhiqizwa okunamandla kwe-ROS. Ikhono le-copper (II) chelates lokugqugquzela ukukhiqizwa kwe-hydroxyl radical in situ lapho kukhona i-ascorbic acid ne-hydrogen peroxide yacwaningwa nge-hydroxyl radical assay kusetshenziswa i-Rhodamine B njenge-analogue yezisekelo ze-DNA enamakha. Izifundo ezibophayo ezincintisanayo zinqume ukuhambisana kwama-chelates ensimbi ku-ct-DNA, [Cu(L1)](PF6) inokuhambisana okuphezulu kakhulu okubophayo: 5.91 × 106 M-1.
Izibalo ze-DFT zenziwa kuma-ligands kanye nama-chelates ensimbi ukuze kunqunywe izakhiwo ezilungiselelwe i-geometry-optimized, amaza okudlidliza, amashifu amakhemikhali e-1H kanye ne-13C NMR kanye nokuguqulwa kwe-electronic. Izinga le-B3LYP/6-311G (d,p) lethiyori lasetshenziselwa ama-ligands, ithusi(II) ne-nickel(II) chelates kanye nezinga le-B3LYP/LanL2DZ lethiyori ye-palladium(II) chelates. Indlela ye-TD-DFT isetshenziselwe izibalo zamandla. Imiphumela yokuhlolwa nebaliwe yaqhathaniswa lapho kwenzeka khona, futhi kwatholakala ukuhlobana okunengqondo.
I-cytotoxicity yama-chelates amahlanu asekelwe ku-amide yahlolwa ngokumelene nemigqa yeseli yomdlavuza wabantu emine, okuyi-A549, TK-10, HT29 kanye ne-U251, kusetshenziswa i-MTT assay. Ama-chelate ahloliwe abonise umsebenzi omuhle wokulwa nomdlavuza ngamavelu amaphakathi we-IC50 ngokumelene nemigqa yeseli yomdlavuza emine kusukela ku-ca. 12 kuya ku-35 μM. Okubalulekile, kwatholakala ukuthi inhlanganisela ye-ion yethusi (II) kanye ne-ligand yayibalulekile ekuthuthukisweni kwe-cytotoxicity. Inkimbinkimbi [Cu(L1)] (PF6) ikhonjwe njengekhandidethi yesidakamizwa esihamba phambili ngokususelwe ekuhlobaneni okuphezulu kwe-DNA kanye ne-cytotoxicity. Le nhlanganisela ibiyi-cytotoxic kakhulu ibheke kumugqa weseli we-glioblastoma u-U251 onenani le-IC50 elingu-7.59 μM. Ama-chelate asekelwe ku-imine ahlolelwa imigqa emithathu yamangqamuzana omdlavuza womuntu: i-MDA-MB, i-HELA, ne-SHSY5Y, kanye nolayini wamaseli womuntu onempilo, i-HEK293. Inkomba yokukhetha yalawa ma-chelates we-neoplastic ngokumelene nomugqa weseli onempilo ibaliwe. Ama-chelates asekelwe ku-imine abonise ukukhetha okuphezulu kumdlavuza webele we-triple-negative MDA-MB, ukuhleleka kobukhulu obunobuthi obuningi engqamuzaneni yesimila kunaleyo enempilo. Le nkomba yokukhetha ithuthukiswe kakhulu kune-cisplatin. Ukuhlolwa kwe-gel mobility shift assay kuphenye ukusebenzisana phakathi kwe-copper(II) chelates ne-plasmid DNA.
I-in vivo biodistribution ye-[Cu(L1)](PF6) inqunywe kusetshenziswa i-analogue ene-radiolabelled ye-copper-64 ye-[Cu(L1)]Cl ne-microPET-CT scanning. Ucwaningo lokuqala lwe-biodistribution luphakamise ukuthi inkimbinkimbi inokusimama okuhle kwe-serum futhi yabonisa ukuthi kwakungekho ukuqoqwa okuphawulekayo kunoma yiziphi izitho. Ucwaningo olwalandela lwaluhilela imodeli ye-xenograft esebenzisa ulayini weseli we-A549 futhi lwabonisa ukuthatheka okubalulekile nokugcinwa kwenkimbinkimbi esimilanjeni. I-cytotoxicity ye-chelate lapho ihlanganiswa nama-isotopes ethusi angewona ama-radioactive kanye nokuthathwa kwe-radiolabelled okulingana nemodeli yesimila kuphakamisa ukuthi le nkimbinkimbi ingaba nesicelo "njenge-ejenti yokwelapha"
Exploring Harry Gwala District Further Education & Training mathematics teachers' experiences of enhancing their competencies of teaching Euclidean geometry proofs during the Corona virus pandemic lockdowns.
No full textMasters Degree. University of KwaZulu-Natal, Durban.The 21st century is characterised by substantial societal, economic, and technological changes, fostering an era of continual evolution and innovation. These transformations pose acknowledged challenges, all of which were emphasised by the disruptions triggered by the COVID-19 pandemic and subsequent lockdowns. This phenomenological case study investigated teachers' experiences of enhancing their competencies of teaching Euclidean geometry proofs during the COVID-19 pandemic lockdowns, a period when face-to-face workshops were prohibited. Data was collected through semi-structured questionnaires administered to 35 mathematics teachers across 15 schools in Harry Gwala District, KwaZulu-Natal. Additionally, three Further Education and Training (FET) mathematics teachers underwent in-depth interviews during the data collection process. Employing a mixed-method approach, teachers were purposively selected from four circuits within the Harry Gwala District, aligning with the interpretive paradigm. Quantitative data was organised using the technological pedagogical and content knowledge (TPACK) framework, while qualitative data underwent interpretative phenomenological analysis. The study found significant challenges in online teaching, particularly in deep rural areas, due to factors such as poor network coverage, limited data availability, scarce resources, low socio-economic status of learners, and negative learner attitudes. Despite these challenges, teachers utilised various digital tools and platforms, including WhatsApp, YouTube, virtual workshops, Google Classroom, Sketchpad, GeoGebra, and smartboard softwares. These tools played a crucial role in enhancing teachers' understanding of teaching Euclidean geometry proofs during COVID-19 lockdowns, improving communication skills and technological pedagogical knowledge. Overall, the strategic use of these digital resources elevated teaching competencies despite uncertainties during the lockdown period. The findings of this study offer practical, empirically based guidelines for education stakeholders and educators seeking to enhance teachers' competencies in online teaching. Understanding how teachers navigated the challenges of online teaching within the context of geometry education during these unique circumstances offers invaluable insights into effective strategies and practices for teaching in similar scenarios.Masters Degree. University of KwaZulu-Natal, Durban
Natural sciences teachers understand and practice inquiry-based science teaching in a primary school: a case study project
No full textDoctoral Degree. University of KwaZulu-Natal, Durban.Primary school natural sciences teachers are as per the curriculum policy documents required to possess the skills, knowledge, and attitudes to engage learners in the subject (Natural Sciences). The researcher used a case study strategy to investigate how grades 6 and 7 natural sciences teachers understood and practised inquiry-based science teaching (IBST), in the process of teaching the subject to their learners. The social constructivist theory of Vygotsky as a theoretical framework underpinned this research. Five grades 6 and 7 natural sciences teachers from a primary school located in the district of Pinetown Department of Basic Education, KwaZulu-Natal were purposefully selected and participated in the study. The research methods employed to generate data included the teachers’ biography and their responses to teaching scenario-based questions from questionnaires, individual semi-structured interviews, which was followed by focus grouping discussions. The five participants responded
to the questions that explored their understandings and practices of IBST. The findings generated indicated that the natural sciences teachers had different understandings and perceptions of IBST. All participants confirmed attending IBST workshops and trainings. They either viewed IBST as involving learners in creating their understandings of phenomena based on evidence or connected the pedagogy to various types of learner participation in the learning process. They associated IBST with teacher-controlled activities such as experiments, demonstrations, and worksheets, but agreed that teaching natural sciences involved both practical and theoretical lessons. The participants' practice of IBST before the intervention laid more emphasis on the conceptual domain and less emphasis on the knowledgeable application domain. In terms of the IBST's guidance component, they mostly assisted learners in generating judgments that are evidence based. Their understanding regarding the cognitive aspect of inquiry and its methods of application for promoting learning through inquiry-based largely informed how they implemented IBST. After the focus group discussion aimed at providing the participants with interventions, the teachers identified several measures they thought would improve the effectiveness of implementing inquiry-based teaching. The most emphasised issues were the science resources for teaching offered to schools and the implementation of suitable professional programmes that would develop teachers considering the context of their teaching environments. These results are expected to benefit a broad range of audiences, including science teachers, curriculum planners, and science teacher educators, given the dispute involving various interpretations of IBST surrounding this topic in science education
Matters of the mind: analysing the depictions of mental health issues in three contemporary African novels.
No full textMasters Degree. University of KwaZulu-Natal, Pietermaritzburg.This dissertation is a literary analysis, and the selected texts have been examined through the theoretical lenses of postcolonialism, spiritual realism, and liminality. Although issues such as identity, race, and culture are examined in postcolonial literature, not many texts focus on the mental health effects of these issues from an African viewpoint. To better understand the postcolonial experience in terms of mental health, it is important to not use a Western model as a universal measure for mental disorders (Nwoye, 2015). This is because different worldviews influence how mental health is viewed. For example, in the West, mental health issues are largely examined through a “bio-psycho-social” approach (Nwoye, 2015:306), with a distinct focus on the self, whereas the African approach also includes a spiritual element (Laher, 2014; Nwoye, 2015). This spiritual element can be seen in Akwaeke Emezi’s debut novel, Freshwater, which incorporates Igbo cosmology, thus adding a supernatural element to the novel. Irenosen Okojie’s debut novel, Butterfly Fish, also encompasses the supernatural, and this brings up the concept of spiritual realism. The mental health struggles of the characters in these novels are interpreted from both a literal African viewpoint as well as a metaphorical lens which sees the spiritual elements in the novels as representations of the mental health issues faced by the characters. Although Yaa Gyasi’s Transcendent Kingdom does not comprise a mystical element, it does examine mental health struggles that stem from postcolonial issues like identity and racism. All three novels therefore offer an explanation of mental health that is relevant not only to Africans living in the West but also to other Neocolonial populations, including those in Africa
Deep learning framework for speech emotion classification.
No full textDoctoral Degree. University of KwaZulu-Natal, Durban.A robust deep learning-based approach for the recognition and classification of speech emotion is proposed in this research work. Emotion recognition and classification occupy a conspicuous position in human-computer interaction (HCI) and by extension, determine the reasons and justification for human action. Emotion plays a critical role in decision-making as well. Distinguishing among various emotions
(angry, sad, happy, neutral, disgust, fear, and surprise) that exist from speech signals has however been a long-term challenge. There have been some limitations associated with existing deep learning techniques as a result of the complexity of features from human speech (sequential data) which consists of insufficient label datasets, Noise and Environmental Factors, Cross-cultural and Linguistic Differences, Speakers’ Variability and Temporal Dynamics. There is also a heavy reliance on huge parameter tunning, especially for millions of parameters before the model can learn the expected emotional features necessary for classification emotion, which often results in computational complexity, over-fitting, and poor generalization. This thesis presents an innovative deep learning framework-based
approach for the recognition and classification of speech emotions. The deep learning techniques currently in use for speech-emotion classification are exhaustively and analytically reviewed in this thesis.
This research models various approaches and architectures based on deep learning to build a framework that is dependable and efficient for classifying emotions from speech signals. This research proposes a deep transfer learning model that addresses the shortcomings of inadequate training datasets for the classification of speech emotions. The research also models advanced deep transfer learning
in conjunction with a feature selection algorithm to obtain more accurate results regarding the classification of speech emotion. Speech emotion classification is further enhanced by combining the regularized feature selection (RFS) techniques and attention-based networks for the classification of speech emotion with a significant improvement in the emotion recognition results. The problem of misclassification
of emotion is alleviated through the selection of salient features that are relevant to emotion classification from speech signals. By combining regularized feature selection with attention-based mechanisms, the model can better understand emotional complexities and outperform conventional ML model emotion detection algorithms. The proposed approach is very resilient to background noise and cultural differences, which makes it suitable for real-world applications. Having investigated the reasons behind the enormous computing resources required for many deep learning based methods, the research proposed a lightweight deep learning approach that can be deployed on low-memory devices for speech emotion classification. A redesigned VGGNet with an overall model size of 7.94MB is utilized, combined with the best-performing classifier (Random Forest). Extensive experiments and comparisons with other deep learning models (DenseNet, MobileNet, InceptionNet, and ResNet) over three publicly available speech emotion datasets show that the proposed lightweight model improves the performance of emotion classification with minimal parameter size. The research further devises a new method that minimizes computational complexity using a vision transformer (ViT) network for speech emotion classification. The ViT model’s capabilities allow the mel-spectrogram input to be fed into the model, allowing for the capturing of spatial dependencies and high-level features from speech signals that are suitable indicators of emotional states. Finally, the research proposes a novel transformer model that is based on shift-window for efficient classification of speech emotion on bi-lingual datasets. Because this method promotes feature reuse, it needs fewer parameters and works well with smaller datasets. The proposed model was evaluated using over 3000 speech emotion samples from the publicly available TESS, EMODB, EMOVO, and bilingual TESS-EMOVO datasets. The results showed 98.0%, 98.7%, and 97.0% accuracy, F1-Score, and precision, respectively, across the 7 classes of emotion