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A phenological and bioclimatic analysis of honey yield in South Africa

  • Authors: Illgner, Peter Mark
  • Date: 2004
  • Subjects: Bee culture -- South Africa -- Statistics Honeybee -- South Africa Bee culture -- South Africa -- Management Honey plants -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5813 , http://hdl.handle.net/10962/d1007153
  • Description: This study has investigated the interaction between honeybees and their forage plants and the impact of selected climatic variables on honey production in South Africa. Twenty-seven scale-hive records from 25 localities have been used as a measure of colony honey reserves. At least 944 plant species are visited by honeybees in South Africa for their nectar and/or pollen, with more than half providing both rewards. The entire honeybee flora encompasses 532 genera and 137 families. The flowering phenologies of the different reward categories of the indigenous forage plants are all significantly and positively correlated at the 0.05 level. Similarly, species offering both rewards are significantly and positively correlated with the flowering phenology of the null flora. The same results were obtained for correlations between the different reward categories of the exotic forage plants in South Africa. Of the 30 species pairs which fulfilled the criteria for selection, 23 occurred in sympatry, 5 in allopatry and 2 in possible parapatry. There is evidence for both competition and facilitation within different indigenous species pairs. The lack of geographical correlation in the intra-annual variation in honey stores and the near absence of any statistically significant (p < 0.05) honey related intra-annual intracolonial correlations may indicate that the former is more important than the latter for the determination of the level of honey reserves within a colony. Only one statistically significant correlation was found between either scale-hive record from the University of Pretoria Experimental Farm and any of the selected climatic variables. A one month lag period and/or possible seasonal effects were detected for each variable, with the exception of the duration of sunshine, in the autocorrelation analyses. A possible 12 month seasonal period was also identified in the single series fourier analyses for a number of variables. Similarly, 12 months was also the most frequently recurring period in the crossspectral results for the one scale-hive record (H42). Any activities which have an impact on the landscape have the potential to affect honeybees and/or their forage plants. Honeybee crop or plant pollination may also enhance yields for commercial farmers and facilitate rural food security.
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  • Date Issued: 2004

A phenomenological explication of dream interpretation among rural and urban Nguni people

  • Authors: Schweitzer, Robert David
  • Date: 1984
  • Subjects: Nguni (African people) -- Religion Nguni (African people) -- Psychology Dreams Dreams -- Psychological aspects Healing -- South Africa -- Religious aspects
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:3125 , http://hdl.handle.net/10962/d1006189
  • Description: Psychologists investigating dreams in non-Western cultures have generally not considered the meanings of dreams within the unique meaning-structure of the person in his or her societal context. The majority of dream studies in African societies are no exception. Researchers approaching dreams within rural Xhosa and Zulu speaking societies have either adopted an anthropological or a psychodynamic orientation. The latter approach particularly imposes a Western perspective in the interpretation of dream material. There have been no comparable studies of dream interpretation among urban blacks participating in the African Independent Church Movement. The present study focuses on the rural Xhosa speaking people and the urban black population who speak one of the Nguni languages and identify with the African Independent Church Movement. The study is concerned with understanding the meanings of dreams within the cultural context in which they occur. The specific aims of the study are: 1. To explicate the indigenous system of dream interpretation as revealed by acknowledged dream experts. 2. To examine the commonalities and the differences between the interpretation of dreams in two groups, drawn from a rural and urban setting respectively. 3. To elaborate upon the life-world of the participants by the interpretations gained from the above investigation. One hundred dreams and interpretations are collected from two categories of participants referred to as the Rural Group and the Urban Group. The Rural Group is made up of amagqira [traditional healers] and their clients, while the Urban Group consists of prophets and members of the African Independent Churches. Each group includes acknowledged dream experts. A phenomenological methodology is adopted in explicating the data. The methodological precedure involves a number of rigorous stages of explication whereby the original data is reduced to Constituent Profiles leading to the construction of a Thematic Index File. By searching and reflecting upon the data, interpretative themes are identified. These themes are explicated to provide a rigorous description of the interpretative-reality of each group. Themes explicated within the Rural Group are: the physiognomy of the dreamer's life- world as revealed by ithongo, the interpretation of ithongo as revealed through action, the dream relationship as an anticipatory mode-of-existence, iphupha as disclosing a vulnerable mode-of-being, human bodiliness as revealed in dream interpretations and the legitimation of the interpretative-reality within the life-world. Themes explicated within the Urban Group are : the physiognomy of the dreamer's life-world revealed in their dream-existence, the interpretative-reality revealed through the enaction of dreams, tension between the newer Christian-based cosomology and the traditional cultural-based cosmology, a moral imperative, prophetic perception and human bodiliness, as revealed in dream interpretations and the legitimation of the interpretative-reality within the life-world. The essence of the interpretative-reality of both groups is very similar and is expressed in the notion of relatedness to a cosmic mode-of-being. The cosmic mode-of-being includes a numinous dimension which is expressed through divine presence in the form of ancestors, Holy Spirit or God. These notions cannot be apprehended by theoretical constructs alone but may be grasped and given form in meaning-disclosing intuitions which are expressed in the lifeworld in terms of bodiliness, revelatory knowledge, action and healing. Some differences between the two groups are evident and reveal some conflict between the monotheistic Christian cosmology and the traditional cosmology. Unique aspects of the interpetative-reality of the Urban Group are expressed in terms of difficulties in the urban social environment and the notion of a moral imperative. It is observed that cultural self-expression based upon traditional ideas continues to play a significant role in the urban environment. The apparent conflict revealed between the respective cosmologies underlies an integration of traditional meanings with Christian concepts. This finding is consistent with the literature suggesting that the African Independent Church is a syncretic movement. The life-world is based upon the immediate and vivid experience of the numinous as revealed in the dream phenomenon. The participants' approach to dreams is not based upon an explicit theory, but upon an immediate and pathic understanding of the dream phenomenon. The understanding is based upon the interpreter's concrete understanding of the life-world, which includes the possibility of cosmic integration and continuity between the personal and transpersonal realms of being. The approach is characterized as an expression of man's primordial attunement with the cosmos. The approach of the participants to dreams may not be consistent with a Western rational orientation, but nevertheless, it is a valid approach. The validity is based upon the immediate life-world of experience which is intelligible, coherent, and above all, it is meaning-giving in revealing life-possibility within the context of human existence.
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  • Date Issued: 1984

A phenomenological hermeneutic investigation into the psychoanalytic psychotherapist's experience of using the psychoanalytic couch

  • Authors: Milton, Christopher
  • Date: 2004
  • Subjects: Freud, Sigmund, 1856-1939 -- Criticism and interpretation Psychoanalysis Psychotherapy Psychotherapy -- Methods
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:3162 , http://hdl.handle.net/10962/d1007655
  • Description: The aim of this study was to describe and critically explore the psychoanalytic, psychotherapist's lived experience of the technique of using the couch. Through examination of the literature a question was formulated that would disclose the analyst's experience of the technique of using the couch. Four experienced psychoanalytic practitioners who could be operationally defined as 'analysts' were interviewed. Using a phenomenological method the protocols were comprehensively analyzed to produce descriptions of the general structure of the experience. These were then texturally enhanced using interleaved direct citations from the interviews. The structural and textural 'findings ' so produced were then hermeneutically dialogued with contemporary psychoanalytic notions of critical discourse and intersubjectivity. The phenomenological ' findings ' of the study disclosed the meaning of the couch as context-based, paradoxical and ambiguous. The couch was found to be a symbol of the analyst as analyst and the process as authentic analysis. Furthermore, at its best, the couch was found to mediate a mode of being that is containing and intimate and in which psychological life may be evoked, tracked and interpreted. The most significant contributor to this mode of being was found to be privacy, which, in particular, helps the analyst maintain an analytic attitude. The couch was also found to be significantly implicated in the generation of an intersubjective analytic third and to support reverie. These 'findings' were hermeneutically dialogued with literature on the couch as well as contemporary psychoanalytic theoretical notions. The dialogue fell into three foci. The first focus entailed deconstructing the meaning of the couch as context-based and ambiguous and not essential. The second pursued critiques of the role that the couch plays in domination, of its function as a symbol/evocative object and of the way in which it shapes being-together, bodily attunement, privacy, the intersubjective analytic third and reverie. Finally the 'findings' were critically examined in terms of both Lacan's notion 'analytic discourse ' and its role in revealing/concealing the analysand as subject. The study concludes with an examination of its own limitations and suggestions for further research.
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  • Date Issued: 2004

A phenomenological investigation into educational leaders' perceptions of themselves, their followers, and their organisational contexts

  • Authors: Van der Mescht, Hennie
  • Date: 1997
  • Subjects: Educational leadership -- Psychological aspects
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:1697 , http://hdl.handle.net/10962/d1003580
  • Description: Leadership is a richly researched ana widely covered topic, attracting the attention of virtually every discipline within the human sciences. Research which focuses on leadership within an educational context is, however, a relatively recent development. Most of the leadership research conducted in this century has been driven by the needs of industry. Consequently, leadership theories have tended to emphasise the instrumentality, measurability and effectiveness of leadership. Leadership models, intent on being prescriptive and 'learnable', have been inclined to oversimplify the complexity of the leadership phenomenon. Another factor which accounts for these features is the research approach adopted by researchers, which has largely been positivistic. This study is an attempt to investigate the underlying dynamics of educational leadership. It is an in-depth study of five educational leaders' perceptions of themselves as leaders, of the people with whom they interact, and of the organisations within which they work. The study is conducted along the lines suggested by phenomenology, a highly qualitative, anti-positivistic research approach, which encourages the researcher to set aside pre-conceived notions of the phenomenon, and to describe what is found exactly as it presents itself. My findings have highlighted a wide and richly varied range of psychological, emotional and cultural factors which seem to play significant roles in how leaders perceive themselves, others and their environments. Most of these factors have been either entirely ignored or very scantily covered in mainstream leadership literature. Educational leadership emerges as a complex, virtually undefinable phenomenon; new and challenging research approaches and methods have the potential for increasing our understanding of how leaders lead, which in turn will have implications for leadership education and selection.
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  • Date Issued: 1997

A phenomenological investigation into lecturers' understanding of themselves as assessors at Rhodes University

  • Authors: Grant, Rose
  • Date: 2005
  • Subjects: Curriculum-based assessment -- South Africa Education, Higher -- South Africa -- Evaluation Educational tests and measurements -- South Africa Education, Higher -- Evaluation Case studies Universities and colleges -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:1315 , http://hdl.handle.net/10962/d1003948
  • Description: This thesis sets out to obtain an understanding of what it means to be an assessor in higher education, more especially within the Rhodes University context. The concept of assessment, a highly contentious and complex issue, is examined against a background of competing understandings of the nature and purpose of higher education, including the striving for excellence versus the call to more equitable ideals associated with a mass higher education and training system. An overview of salient issues is presented in which both traditional and alternative paradigms of measurement and assessment theory are explored with a view to considering foundational principles upon which sound assessment practice should be based. Specific methods and instruments of assessment are examined with the purpose of evaluating their potential for empowering students as active participants in their own learning and in the assessment process. In a field in which much of the literature seeks improved assessment merely through the administration of increasingly sophisticated assessment techniques, a phenomenological investigation offered a unique way of understanding the meaning assessors make of their practice. Making use of in-depth interviews with five lecturers at Rhodes University the researcher, interacting in a personal manner with people not viewed as experimental objects but as human subjects, assisted participants in moving towards non-theoretical descriptions that accurately reflected their experience. Insights contained in the data were synthesised and integrated into a consistent description of the essential nature of the experience, the primary endeavour of the phenomenologist being to transform naïve experience into more explicitly detailed conceptual knowledge. The essence of how these educators understand themselves as assessors at Rhodes University is perhaps best encapsulated by a considerable sense of agency or initiative on their part. While participants make use of a variety of assessment strategies, they are conscious that assessment cannot be viewed in isolation from other aspects of their teaching and the curriculum. Not only do they make use of different assessment methods but, conscious of accommodating the diverse needs of students, understand their responsibility in terms of providing learning opportunities to assist students in meeting the course outcomes and fulfilling their potential. Rather than allowing pressures from within and outside of the academy to dictate, these lecturers, with significant hard work, courage and a capacity for reflective practice, have embraced the challenges associated with higher education in a state of transition.
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  • Date Issued: 2005

A phenomenological investigation into the psychoanalytic psychotherapist's experience of identifying, differentiating and processing the patient's transference-based and reality-oriented reactions

  • Authors: Danilewitz, Larry Mark
  • Date: 1993
  • Subjects: Reality therapy Transference (Psychology) -- Therapeutic use
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:2960 , http://hdl.handle.net/10962/d1002469
  • Description: The aim of this study was to describe the psychoanalytically-oriented therapist's experience of identifying, differentiating and processing the patient's transference-based and reality-oriented reactions. In order to investigate the therapist's lived experience of being receptive to the total communication of the patient in the analytic situation, the researcher adopted the empirical phenomenological method. This descriptive and intuitive method grounded the researcher in the concreteness of the everyday life-world of the therapist, and enabled him to explicate the therapist's immediate, pre-theoretical experiences of his patient. The appropriate central research question, formulated to elicit the experience of this phenomenon, emerged through the process of enquiry during the pilot study. Thirteen experienced, psychoanalytically-oriented psychotherapists were interviewed and the five protocols considered most revelatory of the phenomenon under investigation were analyzed in detail. The remaining eight protocols were used to illuminate central themes and to clarify areas of uncertainty during the phase of formal explication. The central findings revealed that the oscillating process of the therapist as he shifts from being immersed in the world of his patient to being in a position of observation and self reflection is the fulcrum around which he evaluates the nature of his patient's communications. During this ongoing process of discrimination, living in duality, the therapist comes to experience himself as a patient scrutinized by his own and his patient's confrontations. His journey of disentanglement, the endeavour to differentiate his responses from his patient's actions, is dependent on his ability to engage in honest selfreflection and to access his pre-theoretical and articulated cognitions of his patient. This allows him to acknowledge his own role in what has unfolded interpersonally and to appropriate his previously denied feelings for and attitudes towards his patient, a prerequisite for the accurate and full appraisal of the nature of his patient's communications. Forsaking fixed judgements, the therapist becomes open to the confluence between the reality-oriented responses and transference-based reactions of his patient. This salient discovery, when dialogued with the literature, reinforced the theories of Greenson and Langs that not all the interactions between the patient and the analyst/therapist are transference-based and that it is therefore imperative that the analyst/therapist reflect on his participation in the analytic situation.
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  • Date Issued: 1993

A phenomenological investigation into the psychotherapist's experience of identifying, containing and processing the patient's projective identifications

  • Authors: Thorpe, Mark Richard
  • Date: 1989
  • Subjects: Psychotherapist and patient Psychotherapy Methods
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:3071 , http://hdl.handle.net/10962/d1002580
  • Description: The aim of the study was to describe the therapist's lived experience of identifying, containing and processing the feelings, thoughts or fantasies evoked in him by the patient's projective identifications. A question which would elicit the experience of this phenomenon was formulated by examining case histories, and modified through the use of individual pilot studies. Fifteen experienced, psychoanalytically oriented psychotherapists were interviewed. The eight psychologically richest accounts were chosen for the study. Using the empirical phenomenological method, the four protocols that most clearly reflected the phenomenon were analysed in detail, while the remaining four were used to clarify areas of uncertainty. Projective identification is conceptualised as the process whereby the patient coerces the therapist to embody an un-appropriated aspect of his (patient's) world. The context of processing a patient's projective identification was discovered to be such that the therapist finds himself coerced to embody an incongruent, unfamiliar, confusing and inauthentic state of being which is consonant with the patient's perception of him. The discomfort of the experience leads the therapist to bring to awareness and thematise his feeling-state. He alternates between avoiding this state of being, which results in conf1ict with the patient and the therapist's own values, and appropriating it, which feels inauthentic. The therapist moves from a position of trying to understand the experience in relation to his own world, to the realisation that it is co-determined by the patient. From a position of reflective distance he re-appropriates aspects of his world that were closed to him while under the influence of the patient, in addition to appropriating previously unowned aspects. The therapist dialogues these appropriations with the invoked feelings, allowing him to differentiate those aspects of his feeling-state which are authentically his from those which are unowned aspects of the patient's aspects of his world that were closed to him while under the influence of the patient, in addition to appropriating previously unowned aspects. The therapist dialogues these appropriations with the invoked feelings, allowing him to differentiate those aspects of his feeling-state which are authentically his from those which are unowned aspects of the patient's world that he has been forced to embody. Through this process the therapist clarifies and gives meaning to his feelings. The therapist fee1s re1ieved and lighter, when in the service of the therapy, he temporarily gives himself over to the patient's experience of him, without feeling drawn to either disowning or appropriating it, while simultaneously remaining open to his own authentic reality. These findings were dialogued with the literature on projective identification.
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  • Date Issued: 1989

A phenomenological investigation into undergraduate students' experience of acquiring the discourse of engineering

  • Authors: Van Heerden, Karen Ilse
  • Date: 2001
  • Subjects: Education, Higher -- South Africa Students -- Attitudes Academic writing -- Study and teaching -- South Africa English language -- Rhetoric -- Study and teaching -- South Africa Technical writing -- Study and teaching
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:1698 , http://hdl.handle.net/10962/d1003581
  • Description: The area of discourse acquisition and writing in higher education has become a much researched field. In South Africa the interest in discourse acquisition and writing has been partly in response to the change in student profile, particularly over the past ten years. While South African researchers and academics are increasingly focusing their interest in discourse acquisition and writing on the unique circumstances here, they rely on theories based on research done in very different social contexts. These theories are not necessarily universally appropriate. South Africa is currently undergoing a period of transformation in higher education aimed at greater access and equity for black students and academics. The accompanying sense of frustration and disillusionment among students and academics underlines the need to reappraise all aspects of higher education. Much of the research on discourse acquisition and writing is undertaken in arts programmes: vocational fields - such as engineering education - tend to be neglected. If the envisaged growth in science and engineering education is to be realised, it is essential that research in discourse and writing be undertaken in engineering programmes. This study investigates discourse acquisition as experienced by students in a South African engineering faculty. The experiences of six final year technikon students are investigated to gain a better understanding of what it means to acquire the discourse of engineering. The phenomenological method used requires that the researcher suspends or brackets a priori theoretical notions or pre-conceptions so that that which the students experience, rather than what the researcher expects in terms of theory, can emerge. What emerges from the students' experiences is partially congruent with established discourse and writing theories. However, some of the student experiences of discourse acquisition differ in significant ways from what is described in mainstream writing and discourse acquisition theory. The differences in the manner in which these students experience their acquisition of engineering discourse leads to a new understanding of the phenomenon. The students do not experience the alienation or struggle described in mainstream theoretic accounts of discourse acquisition. Students' approaches to writing are affected by their awareness of their multiple identities and the different locations in which they learn. Their approaches to writing are significantly different in some respects from descriptions in mainstream theories in some respects. The description of their experiences gives a different understanding of what it means to acquire the discourse of engineering, and may contribute to the reappraisal of engineering education in a contemporary South African context.
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  • Date Issued: 2001

A phenomenological study of how South African entrepreneurs experience and deal with ethical dilemmas

  • Authors: Robinson, David Alan
  • Date: 2003
  • Subjects: Entrepreneurship -- South Africa Business ethics -- South Africa Decision making -- Moral and ethical aspects
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:1175 , http://hdl.handle.net/10962/d1002791
  • Description: This research sets out to examine how entrepreneurs experience and deal with ethical dilemmas. An entrepreneur is defined as a person who creates something of value and assumes the risk of establishing and managing a business around it. An ethical dilemma comes about when the entrepreneur must choose between alternatives and where the morally correct choice is unclear. This may be due to conflicting personal values or loyalties, tensions arising out of the realization that the moral action is not in line with his self-interest, cross-cultural conflict, or moral ambiguity. Because of the nature of entrepreneurship, the entrepreneur typically lives with ever-present threats arising from limited resources, competition, and the risk of business failure. His actions must simultaneously ensure survival, maximize profit, limit risk, counter threats, optimize the use of resources, and reward him with a feeling of satisfaction. It is hardly surprising that conflicting priorities sometimes ensue. It is also widely believed that these entrepreneurial pursuits supersede the more general need to act in morally appropriate ways. This is a phenomenological study, based on interviews with seven entrepreneurs in established service-oriented ventures. They were asked to describe their business, any dilemmas they have experienced, how they were handled, and what challenges they experience as entrepreneurs in South Africa today. Using phenomenology as my vehicle for data collection and analysis, I sought to enter the lived-worlds of my participants to discover the essence of how ethical dilemmas are experienced in the entrepreneurial milieu. The study’s findings reflect that each entrepreneur has a distinctive world-view, which is represented by a complex mosaic of virtue ethics, deontology, utilitarianism and metaethical perspectives. The permutations are numerous, thus negating the possibility of typecasting entrepreneurs. Instead this research introduces the reader to aspects of entrepreneurial reality such as the complexity of cultural diversity, the freedom to limit the amount of personal energy given to business, and the existence of a more sensitive, searching inner soul beneath the apparent hard-nosed business-oriented public image. While examining entrepreneurial dilemmas in depth, this research introduces the dilemma drum as a tool to portray the argument form of any dilemma by making explicit the ethical component inherent in every business decision and facilitating its effective resolution in a non-prescriptive way. The findings identify certain individual characteristics of participant entrepreneurs that are unlike anything in the mainstream literature, dispelling notions of the entrepreneur as a societal misfit, an essential innovator with vision and flair, or a compulsive risk-taker, while confirming success as the key motivator rather than money per se, the importance of significant others, and the influence of culture and gender. They provide fresh insights into the psyche of the entrepreneur, which include: the existence of inner conviction - marrying the concept of goal-directedness with that of making a contribution to society; exercising the virtues in order to support a delicate balance between business and ethical imperatives; learning to respect energy flow; an alternative morality based on attracting and allowing benevolent or serendipitous events to happen naturally and redefining success as ‘being able to create what is needed as and when needed’; focusing one’s energy on the telos; developing a personal marketing formula suited to a culturallydiverse society; and the anxiety associated with being out-there on one’s own. The general statement, which is ultimately distilled from the seven situated descriptions, introduces a theory of entrepreneurial ethics that presents a new and different view of the lived-world of entrepreneurship, consisting of: Firstly, the key components of entrepreneurial success – having clear goals, energy, making a contribution to society, being connected, getting others on board, and work as an extension of self; secondly, what drives entrepreneurs – goal-orientation, sense of personal excitement, inner conviction, autonomy, and external recognition of success; thirdly, the entrepreneurial ethic – concern for credibility, commitment to service, contributing to quality of life; fourthly, the nature of entrepreneurial dilemmas - conflicting responsibilities, authenticity and credibility, risk and expansion, and awareness of diversity; fifthly, how entrepreneurs deal with ethical issues in their own distinctive ways – by holding fast to authentic virtues, bowing to community expectations, avoiding friction, adopting a ‘come-what-may’ or ‘what’s in it for me’ attitude, or pursuing a higher purpose where both parties benefit; sixthly, entrepreneurs’ world -views – beliefs, goals, ways of deriving satisfaction, virtuous behaviour; pen-ultimately, the challenges facing entrepreneurs in South Africa – overcoming the legacies of apartheid, containing crime, fostering an acceptable business ethic, and facilitating reconciliation between ethnic groups; and lastly, finding the power within – that illusive entrepreneurial spirit – self-reliance, looking beyond immediate obstacles, grasping opportunities, and understanding serendipity.
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  • Date Issued: 2003

A phenomenological study of women primary school heads' experiences as educational leaders in post colonial Zimbabwe

  • Authors: Muzvidziwa, Irene
  • Date: 2013-06-26
  • Subjects: Educational leadership -- Zimbabwe Women school administrators -- Zimbabwe School management and organization -- Zimbabwe Women in education -- Zimbabwe
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:1949 , http://hdl.handle.net/10962/d1008200
  • Description: This research study was carried out in order to gain an understanding of the experiences of women primary school heads, their perceptions of their roles as leaders, the challenges they face and how they dealt with them. The study focused on the lived experiences of five women in Zimbabwe's primary schools. Literature relating to the issues and experiences of women in educational leadership within school contexts and the conceptual framework is examined. The importance of leadership has been emphasised in the literature of school effectiveness. Leadership theories tended to emphasise measurability and effectiveness of leadership, oversimplifying the complexity of leadership phenomenon. These features reflect research approach adopted by researchers from a positivist orientation. This study is an in-depth qualitative study conducted along the lines suggested by a phenomenological-interpretivist design with emphasis on rich contextual detail, close attention to individual's lived experience and the bracketing of pre-conceived notions of the phenomenon. Views and experiences based on the participants' perspectives are described through in-depth interviews which were dialogical in nature. Through this approach, I managed to grasp the essences of the lived experiences of women The research highlights the women's perceptions of themselves as educational leaders. What emerges is the variety of approaches to handling challenges. My findings show a rich and diverse culture of creativity in the way participants adopted a problem-solving strategy, which is not reflected in the mainstream leadership. Though educational leadership emerges as a complex phenomenon, with alternative approaches to educational research, there is high potential for increased understanding of woman's leadership, its importance and implications for school. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
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A physico-chemical investigation of refractory hard metals

  • Authors: Philip, Hamish Ian
  • Date: 1973
  • Subjects: Refractory materials Heat resistant alloys
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4441 , http://hdl.handle.net/10962/d1007630
  • Description: In this investigation, the resistivity of vanadium nitride at elevated temperatures has been measured using a resistance bridge based on the Dauphinée/Mooser (1955) chopper system. In general, an almost linear increase of resistivity with temperature was observed for VN, but at certain temperatures, deviations from linearity (anomalies) were observed, these have been classified into three types. Attempts have been made to correlate the anomalous behaviour and temperature coefficients of resistivity with the ambient atmospheres and with the impurities, (especially oxygen), stoichiotmetry and density of this material. Oxygen and excess nitrogen appear to be electron donors in their effects on VN and result in a decrease in the slope of resistivity vs temperature curves. Oxygen and excess nitrogen also appear to increase the overall resistivity due to an increase in defect concentration. No effects due to the ambient atmosphere have been observed in the case of hot-pressed samples. lndicating that reaction can only occur if the reacting gases can reach the interior of the samples.
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  • Date Issued: 1973

A physiological study on a commercial reef fish to quantify the relationship between exploitation and climate change resilience

  • Authors: Duncan, Murray Ian
  • Date: 2019
  • Subjects: Chrysoblephus laticeps -- Climatic factors , Chrysoblephus laticeps -- Physiology , Sparidae -- South Africa -- Climatic factors , Reef fishes -- South Africa -- Climatic factors , Fish populations -- South Africa -- Climatic factors , Fish populations -- Measurement , Fish populations -- Monitoring , Fisheries -- South Africa -- Environmental aspects , Ocean temperature -- Physiological effect -- South Africa
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/76541 , vital:30599
  • Description: The persistence of harvested fish populations in the Anthropocene will be determined, above all, by how they respond to the interacting effects of climate change and fisheries exploitation. Predicting how populations will respond to both these threats is essential for any adaptive and sustainable management strategy. The response of fish populations to climate change is underpinned by physiological rates and tolerances, and emerging evidence suggests there may be physiological-based selection in capture fisheries. By quantifying important physiological rates of a model species, the endemic seabream, Chrysoblephus laticeps, across ecologically relevant thermal gradients and from populations subjected to varying intensities of commercial exploitation, this thesis aimed to 1) provide the first physiologically grounded climate resilience assessment for a South African linefish species, and 2) elucidate whether exploitation can drive populations to less physiologically resilient states in response to climate change. To identify physiologically limiting sea temperatures and to determine if exploitation alters physiological trait distributions, an intermittent flow respirometry experiment was used to test the metabolic response of spatially protected and exploited populations of C. laticeps to acute thermal variability. Exploited populations showed reduced metabolic phenotype diversity, fewer high-performance aerobic scope phenotypes, and a significantly lower aerobic scope curve across all test temperatures. Although both populations maintained a relatively high aerobic scope across a wide thermal range, their metabolic rates were compromised when extreme cold events were simulated (8 °C), suggesting that predicted future increases in upwelling frequency and intensity may be the primary limiting factor in a more thermally variable future ocean. The increment widths of annuli in the otoliths of C. laticeps from contemporary and historic collections were measured, as a proxy for the annual growth rate of exploited and protected populations. Hierarchical mixed models were used to partition growth variation within and among individuals and ascribe growth to intrinsic and extrinsic effects. The best model for the protected population indicated that the growth response of C. laticeps was poorer during years characterised by a high cumulative upwelling intensity, and better during years characterised by higher mean autumn sea surface temperatures. The exploited population growth chronology was too short to identify an extrinsic growth driver. The growth results again highlight the role of thermal variability in modulating the response of C. laticeps to its ambient environment and indicate that the predicted increases in upwelling frequency and intensity may constrain future growth rates of this species. A metabolic index (ϕ), representing the ratio of O2 supply to demand at various temperatures and oxygen concentrations, was estimated for exploited and protected populations of C. laticeps and used to predict future distribution responses. There was no difference in the laboratory calibrations of ϕ between populations, and all data was subsequently combined into a single piecewise (12 °C) calibrated ϕ model. To predict the distribution of C. laticeps, ϕ was projected across a high-resolution ocean model of the South African coastal zone, and a species distribution model implemented using the random forest algorithm and C. laticeps occurrence points. The future distribution of C. laticeps was estimated by predicting trained models across ocean model projections up to 2100. The best predictor of C. laticeps’ current distribution was minimum monthly ϕ and future predictions indicated only a slight range contraction on either edge of C. laticeps’ distribution by 2100. In order to provide policy makers, currently developing climate change management frameworks for South Africa’s ocean, with a usable output, the results of all research chapters were combined into a marine spatial model. The spatial model identified areas where C. laticeps is predicted to be resilient to climate change in terms of physiology, growth and distribution responses, which can then be prioritised for adaptation measures, such as spatial protection from exploitation. While these results are specific to C. laticeps, the methodology developed to identify areas of climate resilience has broad applications across taxa. From a global perspective, perhaps the most salient points to consider from this case study are the evidence of selective exploitation on physiological traits and the importance of environmental variability, rather than long-term mean climate changes, in affecting organism performance. These ideas are congruent with the current paradigm shift in how we think of the ocean, selective fisheries, and how they relate to organism climate resilience.
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  • Date Issued: 2019

A political discourse analysis of social memory, collective identity and nation-building in the Sunday Mail and the Standard of Zimbabwe between 1999 and 2013

  • Authors: Santos, Phillip
  • Date: 2017
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/41753 , vital:25130
  • Description: Although much effort has been expended on studying many sites of social memory, little attention has been directed at the media’s work of memory, especially in post-colonial Africa. The media’s work of memory is important because of its social standing as a communicative and cultural institution, and because social memory is imbricated in processes of both collective identity formation and nation-building which partly shape patterns of economic distribution, recognition, and representation in society. It is in this context that this study shows how Zimbabwe’s The Sunday Mail and The Standard newspapers used social memory to construct the country’s national identity between 1999 and 2013 in the context of a socio-economic and political crisis for the country’s poly-racial, and poly-ethno-linguistic communities. The study also explores how these newspapers worked as memory sites through their construction of Zimbabwe’s national identity during the period under study. It achieves these tasks by analysing how these newspapers reported on such issues as Zimbabwe’s colonial history, the country’s narrative of decolonisation, the Gukurahundi narrative, the land reform process, elections and independence celebrations. The study takes a critical realist approach to qualitative research, and uses Fairclough and Fairclough’s (2012) method of political discourse analysis as well as Aristotle’s approach to rhetoric for a close reading of the sampled newspaper articles. It is informed by Nancy Fraser’s Theory of Justice, Chantal Mouffe’s Model of Agonistic Pluralism, and Jurgen Habermas’s Discourse Ethics Theory. The study concludes that these two newspapers actively use social memory to construct versions of national identity for specific socio-political and economic ends. Editorials and opinions from The Sunday Mail, which construct Zimbabwean-ness in nativist terms represent the hegemonic appropriation of social memory to construct a sense of Zimbabwean nationhood. In contrast, The Standard uses social memory to construct Zimbabwean-ness in modernist terms with citizenship as the core organising principle of belonging. The political discourse analysis of The Sunday Mail’s and The Standard’s evocation of social memory shows that the two newspapers reflect the tension between indigenist and universalist imaginaries of belonging in Zimbabwe. But the newspapers’ construction of belonging in Zimbabwe is informed by justice claims as seen from each of their political standpoints. As such, their respective definitions of Zimbabweans’ justice claims in terms of their political standpoints, also propose how those justice claims should be addressed and who stands to benefit from them.
  • Full Text:
  • Date Issued: 2017

A preliminary examination of selected biological links between four Eastern Cape estuaries and the inshore marine environment

  • Authors: Vorwerk, Paul D
  • Date: 2007
  • Subjects: Estuaries -- South Africa -- Eastern Cape Marine fishes -- South Africa -- Eastern Cape Marine ecology -- South Africa -- Eastern Cape Estuarine ecology -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5747 , http://hdl.handle.net/10962/d1005434
  • Description: The coastal transition zone (CTZ), which links the terrestrial and marine environments, has been identified as a region of high biological diversity and elevated production. Results of studies conducted in the northern hemisphere indicate that the links between estuaries and the adjacent marine environment is critical to ecological functioning within the CTZ. This study assessed the influence of selected estuaries with different hydrodynamic characteristics on the adjacent marine environment along the south-eastern coastline of southern Africa. Four estuaries were examined, including two permanently open systems, the fresh water deprived Kariega and fresh water dominated Great Fish, and two temporarily open/closed estuaries (TOCE), the Kasouga and East Kleinemonde. Results of the study indicated that outflow of estuarine water from the Great Fish Estuary contributed to a plume of less saline water being evident within the adjacent marine environment. The plume of water was associated with increased zooplankton biomass and particulate organic matter (POM) and chlorophyll-a concentrations. Adjacent to the Kariega Estuary, no evidence of fresh water outflow into the marine environment was observed. However, in the sea directly opposite the mouth of the estuary an increase in zooplankton abundance and biomass was evident. Results of numerical analyses indicated that the increase in zooplankton abundance observed adjacent to the mouth of both permanently open estuaries could not be attributed to the export of zooplankton from the estuary, but rather the accumulation of marine species within the region. The mechanisms responsible for this accumulation were not determined, but it was thought to be associated with increased food availability in the estuarine frontal zone. A similar, but less dramatic biological response was also observed in the marine environment adjacent to the two TOCEs. It is suggested that the increase in biological activity within these regions could be ascribed to seepage of estuarine or ground water through the sand bar that separates these estuaries from the sea. Results of stable carbon isotope analyses indicated that both the Great Fish and Kariega estuaries exported carbon to the nearshore marine environment. The area influenced by estuarine derived carbon was dependent on the volume of estuarine outflow to the marine environment. Adjacent to the fresh water dominated Great Fish Estuary, estuarine derived carbon was recorded up to 12km from the mouth, while adjacent to the fresh water deprived Kariega, estuarine derived carbon was only evident directly opposite the mouth. The recruitment of macrozooplankton (> 2cm) into the fresh water deprived Kariega Estuary was in the range recorded for other permanently open southern African estuaries with higher fresh water flow rates. This indicates that the mechanisms which allow estuarine dependent larvae to locate and enter estuaries are not related to fresh water inflow. In conclusion, this study has demonstrated that despite their small size relative to European and North American systems, South African permanently open and temporarily open/closed estuaries also influence biological activity within the adjacent nearshore marine environment.
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  • Date Issued: 2007

A psycho-educational programme to facilitate the mental health of adolescent girls who are victims of verbal bullying

  • Authors: Jacobs, Ruwayda
  • Date: 2012
  • Subjects: Teenage girls -- Mental health -- South Africa , Psychoanalysis , Bullying
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:9946 , http://hdl.handle.net/10948/d1014579
  • Description: Bullying appears to be a worldwide phenomenon. It occurs within schools, homes, and in the community too. Bullying is a form of aggressive behaviour. Female bullying is not so easily noticed, as girls hardly ever use physical forms of aggression. Bullying can have a detrimental effect on the mental health of the victim. The victims of bullying experience symptoms of mental discomfort, which include low self esteem, feelings of helplessness, feelings of worthlessness and inferiority, lack of confidence, isolation, self-conscientiousness; and lastly, this can lead to suicide. Some form of intervention is necessary to provide adolescents with skills to combat bullying and help them to become mentally healthy again. The overall goal of the study was to develop, implement and evaluate a psycho-educational programme for female adolescents in a secondary school setting, in order to assist them in coping with bullying. The objectives of the research study were to: Conduct asituational analysis to identify the mental health needs of adolescent girls, as victimsof bullying. Develop a psycho-educational programme to facilitate the promotion of mental health of those adolescent girls who are victims of bullying. Implement the psycho-educational programme to facilitate coping by adolescent girls who are victims of bullying.  Assess whether the adolescent girls have benefitted from attending the psycho-educational programme. The researcher used a qualitative, explorative, descriptive and contextual design. The research methodology consisted of four phases. In phase one of the research, a situational analysis was done; and the characteristics of mental discomfort exhibited by the victim were identified. The needs of the adolescent girl who has been bullied have already been described. Phase two involved the development of a psycho-educational programme. The information from the situational analysis was used to develop the conceptual framework. The six concepts in the survey list of Dickoff et al. (1968:422) were described as follows: the recipient is the adolescent girl who has been bullied, the agent is an advanced psychiatric nurse, the context is the community and the secondary school where bullying takes place, the dynamics of the intervention constitute the mental discomfort experienced by the adolescent girl. This is what motivates her to participate in the programme. The procedure was identified as the psycho-educational programme, while the terminus or outcome of the intervention for the adolescent girl would be for her to experience mental health after being exposed to the psycho-educational programme. The relationship between the concepts was used to form the mind map of the conceptual framework. This guided the development of the psycho-educational programme. The content of the programme has already been described. In phase three the psycho-educational programme is implemented and in phase four the programme is evaluated. The psycho-educational programme taught the teenage girls skills and it provided them with knowledge to cope better with the bullying. Attending the programme made the teenagers aware that they needed to change to experience mental health and happiness. The empirical study took place in phase four. The data-gathering method in phase four included the conducting of semi-structured interviews with the adolescent girls who participated in the programme, as well as the teachers of these adolescent girls and their parents. Naïve sketches, reflective journals, observations made and field notes formed part of this database. The data was analyzed by means of Tesch‟s descriptive analysis (in Creswell, 2003:192). The participants had to comment on how they were coping after the implementation of the psycho-educational programme. In conclusion, an intervention in the form of the psycho-educational programme was shown to be beneficial to adolescent girls who were victims of bullying, to assist them in coping with the aftermath of being bullied. Recommendations were made to enhance nursing practice, as well as nursing education and nursing research. Keywords: Adolescent girls, bullying, secondary schools, advanced psychiatric nurse, psycho-educational programme, mental health.
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  • Date Issued: 2012

A psychoanalytic hermeneutic investigation of destructive narcissism

  • Authors: De Wit, Estelle
  • Date: 2013-06-04 , 2004
  • Subjects: Narcissism Narcissism -- Treatment Psychoanalysis Death instinct Ego (Psychology) Self psychology
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:3180 , http://hdl.handle.net/10962/d1008055
  • Description: The purpose of this research was to investigate the clinical phenomenon of destructive narcissism. Contemporary Kleinian and neo-Kleinian theoretical perspectives provided the interpretative perspective on the complexities of inaccessible personalities and subtle forms of internal destructiveness. Four research questions were formulated to interrogate the individual and collective experiences of three male patients whose internal worlds seem to be governed by rigid intrapychic structures organized around the dictatorship of a constellation of seemingly impenetrable defensive strategies. These questions were as follows: 1. What emotional states, actions and experiences of self and others characterize the clinical phenomenon designed as destructive narcissism and distinguish it from other forms of character pathology? 2. What early developmental experiences and relationships may have pre-disposed individuals to the development of this type of character pathology? 3. How are the psychodynamic processes of destructive narcissism structured and configured in the psychotherapeutic process and progress? 4. What are the transference/countertransference psychotherapeutic manifestations of the psychodynamics of destructive narcissism? The illustrative-didactic case study method was utilized to discuss pertinent aspects of each patient. This included their early developmental histories, inter- and intrapersonal relationships, their current mental state, defensive strategies and their stated reasons for commencing psychotherapy. In addition, the structure of the psychotherapeutic process with these patients was reviewed in depth. Various psychic and personality features, as unveiled through this process were discussed, as well as the implications of these for the therapeutic endeavor. The features chosen for discussion were: Firstly, the constellation of the internal object world, the capacity for symbolic thought and defensive organizations. Secondly, therapeutic ambivalence, which made psychotherapy untenable, was explored in conjunction with transference/countertransference issues. Thirdly, the shadow sides of psychotherapeutic change with these patients were considered and the issues of therapeutic failure and other treatment possibilities were examined. It was concluded that there need be an important shift with regard to the psychotherapeutic goals for those patients whose condition may be chronic, and for whom it appears that psychotherapy is of little benefit. In essence, the intent of psychotherapy with these patients is to reach the healthy sane patient of the patient within the pathological organization. Attempts to unravel the perverse gratification and protection derived from the domination of the narcissistic structure may not be enough, and the patient's collusion with the internal destructive gang should also be exposed. If this can be achieved, the patient may come to accept the existence of a part of himself as truly destructive. This, in turn, cannot be disowned, therefore the patient has to live with it. Thus, in destructive narcissism, the challenge for the therapist is the extremely difficult task of disentangling the patient's pain from the idealization of internal destructiveness. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
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  • Date Issued: 2004

A psychobiographical case study: Amelia Dyer in a search for glory

  • Authors: April, Heather
  • Date: 2020
  • Subjects: Serial murderers--Psychology
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10948/50857 , vital:43008
  • Description: The study is a psychobiographical case study based on the life of a Victorian baby farmer Amelia Dyer (1837-1896). She was executed for the murder of babies who were placed in her care over a period of 30 years. Psychobiography is a qualitative method of enquiry which explores the life of a unique individual subject through the lens of a psychological theory for the purpose of creating a coherent psychological case study. The psychoanalytic theoretical lens of Karen Horney was used to trace the evolution of Amelia Dyer’s sense of self within the Victorian culture of respectability. Baby farming referred to an unregulated business of adoption and fostering of infants, mostly illegitimate infants for a fee. Insufficient social structures and support for unwed mothers and children encouraged the business practice as women had very little choice for childcare. Baby farming was open to abuse and exploitation and hundreds of babies lost their lives due to insufficient care or infanticide. Amelia Dyer showed special talents and creativity from a young age, was ambitious and wanted to be self-reliant in a culture that did not provide women with opportunities to live out their ambitions. Baby farming became a business venture for her in the early stages of her life which later evolved into sadistic abuse and murder of the infants. Her evolution from a creative and hardworking young girl to a sadistic murderer of children is what qualifies her as a suitable subject for the exploration of Karen Horney’s dynamic theory of neuroses and the development of the neurotic self within culture. Extensive biographical data was collected and processed into salient themes. The study integrates the theory of Karen Horney, the life experiences of Amelia Dyer and Victorian respectability and demonstrates the value of using psychobiography as the method of inquiry into the exploration of the unique individual. The findings of the study demonstrated that Amelia Dyer and her social context were inextricably bound by a vicious cycle of psychic and emotional vi conflicts related to fear, control and self-hatred by the internalization of gender stereotypes and norms. The contribution of the study as a whole rests with its demonstration of the value of a holistic and reflexive exploration of the unique individual woman. It demonstrates the value of Horney’s in-depth theoretical understanding of the ambivalent core of selfhood that lies behind observable acts of behavior. The study as a whole contributes towards building upon holistic and integrative therapeutic frameworks in the understanding of diversity amongst women and mothers in culture.
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  • Date Issued: 2020

A psychobiographical study of Temple Grandin

  • Authors: Wannenburg, Nicola
  • Date: 2018
  • Subjects: Grandin, Temple , Psychology Biographical methods , Psychoanalysis , Autistic women United States Biography , Women animal specialists United States Biography , Developmental psychology , Erikson, Erik H (Erik Homburger), 1902-1994
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/57358 , vital:26877
  • Description: Psychobiographical researchers methodically formulate life histories and interpret them by means of psychological theories. The research typically focuses on exemplary and completed lives. The cases that are studied are usually of individuals who are of particular interest to society as a result of excelling in their particular fields, be they to benefit or detriment of society. Temple Grandin was chosen for this study using purposive sampling as she meets the psychobiographical requirement of being an extraordinary individual. As an individual with autism Grandin faced many challenges growing up. Despite a difficult and absent beginning, Grandin developed into a stable and scientifically creative adult who contributes to society. She excels as an animal scientist and designer of humane livestock handling facilities and has an international reputation for her contribution to the livestock industry and animal welfare. The primary aim of this study is to describe and interpret the life of Temple Grandin through Erikson’s (1950/1973) theory of psychosocial development. A mixed method approach (Yin, 2006) was employed for the conduction of this study. The overarching data processing and analysis guidelines for this study were provided by Miles and Huberman (1994, 2002a, 2002b). The conduction of the processing and analysis of data was aided by Alexander’s (1988, 1990) method of asking the data questions as well as an integration of Yin’s (2014) time series analysis with Erikson’s (1950/1973) triple bookkeeping approach. This study contributes to the development of psychobiographical research in South Africa as well as to personality and developmental theory.
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  • Date Issued: 2018

A psychobiography of Viktor Emil Frankl

  • Authors: Bushkin, Hanan
  • Date: 2020
  • Subjects: Frankl, Viktor Emil
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10948/46440 , vital:39566
  • Description: The first study conducted in South Africa of a prominent figure traces back as far as 1939. Since then, extensive research has been done in the field of psychobiography, resulting in a growing interest in this field and evolving into an established research genre in South Africa. Despite the increase in the use of psychobiographies as a research approach internationally and specifically in South Africa, its use is still considered relatively under-utilised and, therefore, the pursuit of further development of psychobiographies in South Africa is required. In light of South Africa’s effort to promote and advance the use of psychobiographies, South African researchers may be motivated to continue studying significant and exceptional lives in South Africa and abroad. Viktor Frankl was selected for this study based on his uniqueness, significance and his interesting life. He is also considered an exceptional individual who has shaped modern psychological thinking. Frankl had written over 40 books on his theory and many studies have been conducted based on his existential theory. Frankl’s contribution to the academic world has been recognised and acknowledged by significant institutions through his own and others’ research. Although much has been written on the life and work of Frankl, none of the literature utilises specific psychological focus and no psychobiographical study of the life of Frankl exists. Therefore, the researcher selected Frankl as the subject for this psychobiography through purposive sampling. The aim of the study was to provide a psychological exploration and description of Frankl’s life against the backdrop of his socio-cultural context. In order to achieve this aim, the researcher employed two psychological frameworks to guide in the description and exploration of his life. The psychological frameworks included Levinson’s life structure theory of adult development and Frankl’s existential theory. The study aimed to describe Frankl’s development with the use of Levinson’s theory while describing how he attained meaning in his life with the use of his own existential theory. Due to the exploratory-descriptive nature of this study, the objective fell within the inductive research approach. The researcher utilised a systematic coding method to arrange the data. The theoretical framework of Levinson’s life structure theory guided the coding system, as well as the key concepts of Frankl’s existential theory. In addition, the researcher utilised Alexander’s guidelines for the extraction of salient data, together with McAdam’s methods and recommendations for managing the data. Lastly, the researcher followed the 12-step method of conducting a psychobiography, as proposed by Du Plessis. Findings from this study found a correlation between Frankl’s life and the eras and transitional periods as theorised by Levinson’s theory. The findings of this study, therefore, support the use of Levinson’s theory with regards to the time frames and its use in understanding Frankl’s development. Also, the researcher found that Levinson’s theory was useful in understanding Frankl’s personality development within his context throughout his lifespan. With regards to Frankl’s existential theory, the researcher found that the use of the theory was suitable in understanding Frankl’s search for meaning. Frankl’s concepts of freedom of will, will to meaning, meaning of life, existential vacuum, supra-meaning, dimensional ontology, the three triads and noö-dynamics assisted in explaining Frankl’s drive to find meaning in his life, take responsibility to attain such meaning and to strive for transcendence beyond his suffering. The researcher found Frankl’s theory useful in explaining his drive, motives, needs and patterns of behaviour within this context. The holistic and integrative approach of the study allowed for an in-depth exploration and description of Frankl’s life and development within his socio-historical context. In addition to contributing to the existing body of knowledge on Frankl, his life and his theory, the study also contributed to the growing field of psychobiographical research. The study acknowledged and highlighted that further in-depth examination of the lives of extraordinary personalities could significantly contribute to psychobiographical studies. Based on the psychological frameworks used to explore and describe Frankl’s life, recommendations are made for future research.
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  • Date Issued: 2020

A reappraisal of the origin of the Hotazel Fe-Mn Formation in an evolving early Earth system through the application of mineral-specific geochemistry, speciation techniques and stable isotope systematics

  • Authors: Mhlanga, Xolane Reginald
  • Date: 2020
  • Subjects: Manganese ores -- South Africa -- Hotazel , Manganese ores -- Geology , Iron ores -- South Africa -- Hotazel , Iron ores -- Geology , Geochemistry -- South Africa -- Hotazel , Isotope geology -- South Africa -- Hotazel , Geology, Stratigraphic -- Archaean , Geology, Stratigraphic -- Proterozoic , Transvaal Supergroup (South Africa) , Great Oxidation Event
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/146123 , vital:38497
  • Description: Marine chemical sediments such as Banded Iron Formations deposited during the Archean-Palaeoproterozoic are studied extensively because they represent a period in the development of the Earth’s early history where the atmospheric O₂ content was below the present levels (PAL) of 21%. Prior to the Great Oxidation Event (GOE) at ca. 2.4 Ga, highly ferruginous and anoxic marine environments were dominated by extensive BIF deposition such as that of the Griqualand West Basin of the Transvaal Supergroup in South Africa. This basin is also thought to record the transition into the first rise of atmospheric O₂ in our planet, from the Koegas Subgroup to the Hotazel Formation dated at ca. 2.43 Ga (Gumsley et al., 2017). Two drill cores from the north eastern part of the Kalahari Manganese Field characterized by a well-preserved and complete intersection of the cyclic Mn-Fe Hotazel Formation were studied at a high resolution (sampled at approximately one-meter interval). Such high-resolution approach is being employed for the first time in this project, capturing in detail the three manganese rich layers intercalated with BIF and the transitions between these lithofacies. The micro-banded BIF is made up of three major phases, namely Fe-Ca-Mg carbonates (ankerite, siderite and calcite), magnetite, and silicates (chert and minor Fe-silicates); laminated transitional lutite consist of mainly hematite, chert and Mn-carbonates, whereas the manganese ore layers are made up of mostly calcic carbonates (Mn-calcite and Ca-kutnahorite) in the form of laminations and ovoids, while Mn-silicates include dominant braunite and lesser friedelite. All three lithofacies are very fine grained (sub-mm scale) and so petrographic and mineralogical observations were obtained mostly through scanning electron microscope analysis for detailed textural relationships with focus on the carbonate fraction. Bulk geochemical studies of the entire stratigraphy of the Hotazel Formation have previously provided great insights into the cyclic nature of the deposit but have not adequately considered the potential of the carbonate fraction of the rocks as a valuable proxy for understanding the chemistry of the primary depositional environment and insights into the redox processes that were at play. This is because these carbonates have always been attributed to diagenetic processes below the sediment-water interface such as microbially-mediated dissimilatory iron/manganese reduction (DIR/DMR) where the precursor/primary Fe-Mn oxyhydroxides have been reduced to result in the minerals observed today. The carbonate fraction of the BIF is made up of ankerite and siderite which co-exist in a chert matrix as anhedral to subhedral grains with no apparent replacement textures. This suggests co-precipitation of the two species which is at apparent odds with classic diagenetic models. Similarly, Mn-carbonates in the hematite lutite and manganese ore (Mn-calcite, kutnahorite, and minor rhodocrosite) co-exist in laminae and ovoids with no textures observed that would suggest an obvious sequential mode of formation during diagenesis. In this light, a carbonate-specific geochemical analysis based on the sequential Fe extraction technique of Poulton and Canfield (2005) was employed to decipher further the cyclic nature of the Hotazel Formation and its primary versus diagenetic controls. Results from the carbonate fraction analysis of the three lithofacies show a clear fractionation of iron and manganese during primary – rather than diagenetic - carbonate precipitation, suggesting a decoupling between DIR and DMR which is ultimately interpreted to have taken place in the water column. Bulk-rock concentration results for minor and trace elements such as Zr, Ti, Sc and Al have been used for the determination of either siliciclastic or volcanic detrital inputs as they are generally immobile in most natural aqueous solutions. These elements are in very low concentrations in all three lithofacies suggesting that the depositional environment had vanishingly small contributions from terrigenous or volcanic detritus. In terms of redox-sensitive transition metals, only Mo and Co appear to show an affinity for high Mn facies in the Hotazel sequence. Cobalt in particular attains a very low abundance in the Hotazel BIF layers at an average of ~ 4 ppm. This is similar to average pre-GOE BIF in South Africa and worldwide. Maxima in Co abundance are associated with transitional hematite lutite and Mn ore layers, but maxima over 100ppm are seen in within the hematite lutite and not within the Mn ore proper where maxima in Mn are recorded. This suggests a clear and direct association with the hematite fraction in the rocks, which is modally much higher in the lutites but drops substantially in the Mn layers themselves. The similarities of bulk-rock BIF and modern-day seawater REE patterns has been used as a key argument for primary controls in REE behaviour and minimal diagenetic modification. Likewise, the three lithofacies of the Hotazel Formation analysed in this study all share similar characteristics with a clear seawater signal through gentle positive slopes in the normalised abundance of LREE versus HREE. Negative Ce anomalies prevail in the entire sample set analysed, which has been interpreted before as a proxy for oxic seawater conditions. However, positive Ce anomalies that are traditionally linked to scavenging and deposition of primary tetravalent Mn oxyhydroxides (e.g., as observed in modern day ferromanganese nodules) are completely absent from the current dataset. The lack of a positive Ce anomaly in the manganese ore and peak Co association with ferric oxides and not with peak Mn, suggests that primary deposition must have occurred within an environment that was not fully oxidizing with respect to manganese. The use of stable isotopes (i.e., C and Fe) was employed to gain insights into redox processes, whether these are thought to have happened below the sediment-water interface or in contemporaneous seawater. At a small scale, all lithofacies of the Hotazel Formation record bulk-rock δ¹³C values that are low and essentially invariant about the average value of -9.5 per mil. This is independent of sharp variations in overall modal mineralogy, relative carbonate abundance and carbonate chemistry, which is clearly difficult to reconcile with in-situ diagenetic processes that predict highly variable δ¹³C signals in response to complex combinations of precursor sediment mineralogy, pore-fluid chemistry, organic carbon supply and open vs closed system diagenesis. At a stratigraphic scale, the carbonate δ¹³C (-5 to -13‰) variations between the different lithologies could instead represent temporal changes in water-column chemistry against well-developed physico-chemical gradients, depth of deposition and biological processes. The low iron isotope values recorded in the hematite lutite and manganese ore samples can be attributed to fractionation effects of initial oxidation of ferrous iron to form Fe-oxyhydroxides in the shallow parts of the basin, from an already isotopically highly depleted aqueous Fe-pool as proposed previously. The slightly higher but still negative bulk-rock δ⁵⁶Fe values of the host BIF can be attributed to water-column Fe isotopic effects at deeper levels between primary Fe oxyhydroxides and an isotopically heavier Fe(II) pool, which was subsequently preserved during diagenetic recrystallization. All above findings were combined into a conceptual model of deposition for the three different lithologies of the Hotazel Formation. The model predicts that free molecular oxygen must have been present within the shallow oceanic environment and implicates both Mn and Fe as active redox “players” compared to classic models that apply to the origin of worldwide BIF prior to the GOE. The deposition of the Hotazel strata is interpreted to have occurred through the following three stages: (1) BIF deposition occurred in a relatively deep oceanic environment above the Ongeluk lavas during marine transgression, where a redoxcline and seawater stratification separated hydrothermally sourced iron and manganese, in response to an active Mn-shuttle mechanism linked to Mn redox cycling. Abundant ferrous iron must have been oxidized by available oxygen but also by oxidised Mn species (MnOOH) and possibly even some soluble Mn(III) complexes. Through this process, Mn(III) was being effectively reduced back into solution along with cobalt(III), as Mn(II) and Co(II) respectively, thus creating maxima in their concentrations. A drawdown of Fe(OH)₃ particles was therefore the only net precipitation mechanism at this stage. Carbonate species of Fe and the abundant magnetite would possibly have formed by reaction between the ferric hydroxides and the deeper Fe(II) pool, while organic matter would also have reacted in the water-column via DIR, accounting for the low δ¹³C signature of Fe carbonate minerals. (2) Hematite lutite formation would have occurred at a relatively shallower environment during marine regression. At this stage, reductive cycling of Fe was minimal in the absence of a deeper Fe(II) reservoir reacting with the ferric primary precipitates. Therefore, DIR progressively gave way to manganese reduction and organic carbon oxidation (DMR), which reduced MnOOH to form Mn(II)-rich carbonates in the form of kutnahorite and Mn-calcite. Co-bearing Fe(OH)₃ would have precipitated and was ultimately preserved as Co-bearing hematite during diagenesis. (3) Deposition of manganese-rich sediment occurred at even shallower oceanic depths (maximum regression) where aerobic organic carbon oxidation replaced DMR, resulting in Ca-rich carbonates such as Mn-bearing calcite and Ca-kutnahorite, yet with a low carbon isotope signature recording aerobic conditions of organic carbon cycling. Mn(III) reduction at this stage was curtailed, leading to massive precipitation of MnOOH which was diagenetically transformed into braunite and friedelite. Simultaneous precipitation of Co-bearing Fe(OH)₃ would have continued but at much more subdued rates. Repeated transgressive-regressive cycles resulted in the cyclic BIF-hematite lutite- manganese ore nature of the Hotazel Formation in an oxidized oceanic environment at the onset of the Great Oxidation Event, which was nonetheless never oxic enough to drive Mn(II) oxidation fully to its tetravalent state. The mineralogy and species-specific geochemistry of the Hotazel strata, and more specifically the carbonate fraction thereof, appear to faithfully capture the chemistry of the primary depositional environment in a progressively evolving Earth System. This project opens the door for more studies focusing on better constraining primary versus diagenetic depositional 2020 Hotazel Fe and Mn deposition mechanisms of iron and manganese during the period leading up to the GOE, and possibly re-defining the significance of Fe and Mn as invaluable redox proxies in a rapidly changing planet.
  • Full Text:
  • Date Issued: 2020
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