The relevance of career counselling in higher education: a study following students at a South African university
- Authors: Lewis, Christine
- Date: 2023-10-13
- Subjects: Vocational guidance South Africa , Counseling in higher education South Africa , Identity (Psychology) in education , Ethnopsychology , College students South Africa Longitudinal studies
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/432347 , vital:72863 , DOI 10.21504/10962/432348
- Description: Very few students in South Africa (SA) receive adequate career counselling at school and often arrive at institutions of higher learning without a clear sense of what their prospective careers will entail. The limited access to career counselling and assessment is further compounded by criticisms of popular career assessment instruments used in SA, where the primary goal of career counselling and assessment is to match clients to careers for job placement. This approach no longer serves the needs of a diverse SA population and disregards contextual influences on careers. Therefore, a need exists to understand and inform career counselling interventions and to guard against the provision of de-contextualised and contextually insensitive approaches. Moreover, changes in the workplace, where career change has become the norm as the world of work has moved away from stability and permanency to fluidity, calls for a contemporary response from career counselling theories, practitioners as well as researchers, to equip clients with the necessary skills to respond to these changes. Thus, SA institutions of higher learning need to innovate their practices to more inclusively, effectively, and justly serve the needs of a diverse student population for work success in a developing nation and a complex world. This study aimed to evaluate the relevance and effectiveness of a university’s career counselling services from the students’ perspectives. It focuses on gaining an indication of the perceived effectiveness of assessment measures used, and to ascertain the influences that impact on individual students’ career decision-making over the course of undergraduate studies. Due to the increasing recognition for the need to develop a contextualised approach to career development interventions, this study included the SACII, a locally developed interest inventory as part of a career assessment battery, with a group of university students. A pragmatic approach using mixed-methods was used. Multiple case studies of the career trajectories of a cohort of undergraduate students who had undertaken career assessments at the university career centre, were tracked longitudinally over the course of undergraduate studies. Data were generated through vignettes that included the 13 participants' career assessment reports, a service evaluation questionnaire and two successive follow-up interviews. Each participant's first follow-up interview occurred six months after their career assessment feedback session; and the second follow-up was in the final year of undergraduate studies, after eighteen months. Descriptive statistical analysis summarised the basic features of the quantitative data from the evaluation questionnaire. Thematic analysis was used for organisation and analysis of the follow-up interview data. Findings were that the career counselling and assessment facilitated greater self-knowledge in relation to career decision-making, assisted with selecting degree major subjects and enhanced career planning abilities. Using locally developed assessment measures in career counselling proved to be useful. Exploring career development from an overarching developmental contextual framework that is applicable and well-suited to the SA context provided a deeper understanding of contextual influences that impact on students' career decision-making processes. , Thesis (PhD) -- Faculty of Humanities, Psychology, 2023
- Full Text:
Sequence, structure, dynamics, and substrate specificity analyses of bacterial Glycoside Hydrolase 1 enzymes from several activities
- Authors: Veldman, Wayde Michael
- Date: 2022-04-08
- Subjects: Glycosidases , Bioinformatics , Molecular dynamics , Ligands (Biochemistry) , Enzymes , Ligand binding (Biochemistry) , Sequence alignment (Bioinformatics) , Structural bioinformatics
- Language: English
- Type: Doctoral thesis , text
- Identifier: http://hdl.handle.net/10962/233805 , vital:50129 , DOI 10.21504/10962/233810
- Description: Glycoside hydrolase 1 (GH1) enzymes are a ubiquitous family of enzymes that hydrolyse the glycosidic bond between two or more carbohydrates, or between a carbohydrate and a non-carbohydrate moiety. Despite their conserved catalytic domain, these enzymes have many different enzyme activities and/or substrate specificities as a change of only a few residues in the active site can alter their function. Most GH1 active site residues are situated in loop regions, and it is known that enzymes are more likely to develop new functions (broad specificity) if they possess an active site with a high proportion of loops. Furthermore, the GH1 active site consists of several subsites and cooperative binding makes the binding affinity of sites difficult to measure because the properties of one subsite are influenced by the binding of the other subsites. Extensive knowledge of protein-ligand interactions is critical to the comprehension of biology at the molecular level. However, the structural determinants and molecular details of GH1 ligand specificity and affinity are very broad, highly complex, not well understood, and therefore still need to be clarified. The aim of this study was to computationally characterise the activity of three newly solved GH1 crystallographic structures sent to us by our collaborators, and to provide evidence for their ligand-binding specificities. In addition, the differences in structural and biochemical contributions to enzyme specificity and/or function between different GH1 activities/enzymes was assessed, and the sequence/structure/function relationship of several activities of GH1 enzymes was analysed and compared. To accomplish the research aims, sequence analyses involving sequence identity, phylogenetics, and motif discovery were performed. As protein structure is more conserved than sequence, the discovered motifs were mapped to 3D structures for structural analysis and comparisons. To obtain information on enzyme mechanism or mode of action, as well as structure-function relationship, computational methods such as docking, molecular dynamics, binding free energy calculations, and essential dynamics were implemented. These computational approaches can provide information on the active site, binding residues, protein-ligand interactions, binding affinity, conformational change, and most structural or dynamic elements that play a role in enzyme function. The three new structures received from our collaborators are the first GH1 crystallographic structures from Bacillus licheniformis ever determined. As phospho-glycoside compounds were unavailable for purchase for use in activity assays, and as the active sites of the structures were absent of ligand, in silico docking and MD simulations were performed to provide evidence for their GH1 activities and substrate specificities. First though, the amino acid sequences of all known characterised bacterial GH1 enzymes were retrieved from the CAZy database and compared to the sequences of the three new B. licheniformis crystallographic structures which provided evidence of the putative 6Pβ-glucosidase activity of enzyme BlBglH, and dual 6Pβ-glucosidase/6Pβ-galactosidase (dual-phospho) activity of enzymes BlBglB and BlBglC. As all three enzymes were determined to be putative 6Pβ-glycosidase activity enzymes, much of the thesis focused on the overall analysis and comparison of the 6Pβ-glucosidase, 6Pβ-galactosidase, and dual-phospho activities that make up the 6Pβ-glycosidases. The 6Pβ-glycosidase active site residues were identified through consensus of binding interactions using all known 6Pβ-glycosidase PDB structures complexed complete ligand substrates. With regards to the 6Pβ-glucosidase activity, it was found that the L8b loop is longer and forms extra interactions with the L8a loop likely leading to increased L8 loop rigidity which would prevent the displacement of residue Ala423 ensuring a steric clash with galactoconfigured ligands and may engender substrate specificity for gluco-configured ligands only. Also, during molecular dynamics simulations using enzyme BlBglH (6Pβ-glucosidase activity), it was revealed that the favourable binding of substrate stabilises the loops that surround and make up the enzyme active site. Using the BlBglC (dual-phospho activity) enzyme structure with either galacto- (PNP6Pgal) or gluco-configured (PNP6Pglc) ligands, MD simulations in triplicate revealed important details of the broad specificity of dual-phospho activity enzymes. The ligand O4 hydroxyl position is the only difference between PNP6Pgal and PNP6Pgal, and it was found that residues Gln23 and Trp433 bind strongly to the ligand O3 hydroxyl group in the PNP6Pgal-enzyme complex, but to the ligand O4 hydroxyl group in the PNP6Pglc-enzyme complex. Also, His124 formed many hydrogen bonds with the PNP6Pgal O3 hydroxyl group but had none with PNP6Pglc. Alternatively, residues Tyr173, Tyr301, Gln302 and Thr321 formed hydrogen bonds with PNP6Pglc but not PNP6Pgal. Lastly, using multiple 3D structures from various GH1 activities, a large network of conserved interactions between active site residues (and other important residues) was uncovered, which most likely stabilise the loop regions that contain these residues, helping to retain their positions needed for binding molecules. Alternatively, there exists several differing residue-residue interactions when comparing each of the activities which could contribute towards individual activity substrate specificity by causing slightly different overall structure and malleability of the active site. Altogether, the findings in this thesis shed light on the function, mechanisms, dynamics, and ligand-binding of GH1 enzymes – particularly of the 6Pβ-glycosidase activities. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2022
- Full Text:
The mechanisms conditioning doctoral supervision development in public universities across South Africa
- Authors: Motshoane, Puleng Lorraine
- Date: 2022-04
- Subjects: Doctoral students South Africa , Graduate students Supervision of South Africa , Agent (Philosophy) , Public universities and colleges South Africa , Supervisors Training of South Africa , Supervision South Africa , Mentoring in education South Africa
- Language: English
- Type: Doctoral thesis , text
- Identifier: http://hdl.handle.net/10962/232305 , vital:49980 , DOI 10.21504/10962/232305
- Description: This study offers a social realist account of how South African public institutions develop emerging supervisors. The study addresses the need for supervision development across South African public higher education universities. The purpose of the study was to answer the question “What mechanisms condition the development and support of emerging doctoral supervisors across South African public universities?” To examine this question, analytical dualism was used to separate the roles of the ‘people’ (agents) from the ‘parts’ (structure and culture) to examine their interplay. The study was qualitative, and the data was generated through documents, an online survey, and semi-structured interviews. One hundred and eighty-six participants responded to the survey and fifty-four people were interviewed. The participants came from twenty of the twenty-six public higher education universities and represent a large range of disciplines. The study findings revealed that emerging supervisors were often simply ‘thrown into the deep-end’ as they had to work out how to supervise by learning from their students and using the experience gained while they were being supervised. This was experienced as highly problematic by the participants who shared this understanding. Secondly, the findings suggest that where there were developmental events in place, some were not well received. For example where those providing the training were not regarded as credible because they lacked the supervision experience or because the interventions were seen to be too ad hoc and generic. There were calls for more discipline-specific interventions and collaborative spaces where emerging supervisors could engage with experienced supervisors rather than being instructed in a generic best-practice of ‘how to supervise’. The findings indicated that the lines between co-supervision and mentoring were often blurred, and both were used as another form of supervision development. Such relationships provided a useful means for emerging supervisors to come to understand the complex pedagogy of postgraduate supervision but were at times constrained by power imbalances. It was evident across the data that supervision is a special form of teaching and needs to be conceptualised at least in part as a pedagogy. Moreover, the issue of institutional differentiation needs to be considered for the sector to achieve its intended goals of increasing doctoral output and to be able to participate fully in the knowledge economy. , Phuputso ena e fana ka tlaleho ea 'nete ea kahisano ea kamoo litsi tsa Afrika Boroa li ntlafatsang batsamaisi ba ntseng ba hlaha. Phuputso ena e sebetsana le tlhokeho ya ntshetsopele ya bolebedi ho tswa ho diyunibesithing tsa thuto e phahameng tsa setjhaba tsa Aforika Borwa. Sepheo sa phuputso e ne e le ho araba potso e mabapi le "Ke mekhoa efe e behang nts'etsopele le tšehetso ea baokameli ba ntseng ba tsoela pele ho pholletsa le liunivesithi tsa sechaba tsa Afrika Boroa?" E le ho hlahloba potso ena, ho ile ha sebelisoa li-analytical dualism ho arola likarolo tsa "batho" (baemeli) ho "likarolo" (sebopeho le setso) ho hlahloba likamano tsa bona. Thuto e ne e le ea boleng, 'me lintlha li ile tsa hlahisoa ka litokomane, phuputso ea inthaneteng, le lipuisano tse hlophisitsoeng hantle. Barupeluoa ba lekholo le mashome a robeli a metso e tšeletseng ba ile ba arabela phuputsong eo, 'me batho ba 54 ba botsoa. Barupeluoa ba ne ba tsoa liunivesithing tse mashome a mabeli ho tse mashome a mabeli a metso e tšeletseng tsa thuto e phahameng ea sechaba 'me ba emetse mefuta e mengata ea lithuto. Liphuputso tsa phuputso li senotse hore baokameli ba ntseng ba hlaha hangata ba ne ba ‘lahleloa botebong ba pelo kaha ba ne ba lokela ho etsa qeto ea ho laola ka ho ithuta ho liithuti tsa bona le ho sebelisa phihlelo eo ba e fumaneng ha ba ntse ba behiloe leihlo. Phihlelo ena e bile bothata haholo ho barupeluoa ba arolelanang boiphihlelo bona. Taba ea bobeli, liphuputso li fana ka maikutlo a hore ha liketsahalo tsa nts'etsopele li ntse li le teng, tse ling ha lia ka tsa amoheloa hantle, mohlala, hobane ba fanang ka koetliso ba ne ba sa nkoe e le ba ka tšeptjoang hobane ba ne ba se na boiphihlelo ba bolebeli kapa hobane ho ne ho bonahala hore ho na le mehato ea nakoana. . Ho bile le meipiletso ea hore ho be le litšebetso tse khethehileng tsa khalemelo le libaka tse kopanetsoeng moo baokameli ba neng ba ka buisana le baokameli ba nang le phihlelo ho e-na le ho rutoa ka mokhoa o tloaelehileng oa 'ho laola'. Liphuputso li bonts'itse hore litsela tse pakeng tsa ts'ebelisano-'moho le boeletsi hangata li ne li sa hlaka. Ho feta moo, ka bobeli li ne li sebelisoa e le mofuta o mong oa ntlafatso ea tlhokomelo. Likamano tse joalo li ne li fana ka mokhoa oa bohlokoa bakeng sa baokameli ba ba qalang ho utloisisa thuto e rarahaneng ea bolebeli ba morao-rao empa ka linako tse ling ba ne ba sitisoa ke ho se leka-lekane ha matla. Ho ile ha totobala ho pholletsa le data hore tsamaiso ke mokhoa o ikhethileng oa ho ruta 'me o hloka ho nahanoa bonyane e le mokhoa oa ho ruta. Ho feta moo, taba ea karohano ea litsi e lokela ho shejoa hore lekala le fihlele lipheo tsa lona tse reriloeng tsa ho eketsa tlhahiso ea bongaka le ho kenya letsoho ka botlalo moruong oa tsebo. , Thesis (PhD) -- Faculty of Education, Education, 2022
- Full Text: