List of Titles

An investigation into the synergistic association between the major Clostridium cellulovorans cellulosomal endoglucanase and two hemicellulases on plant cell wall degradation

- Beukes, Natasha

Authors: Beukes, Natasha
Date: 2008
Subjects: Clostridium , Cellulose , Hemicellulose , Cellulase , Biomass conversion , Biomass energy -- South Africa , Energy crops -- South Africa , Bagasse -- Biodegradation , Pineapple -- Biodegradation
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:3968 , http://hdl.handle.net/10962/d1004027 , Clostridium , Cellulose , Hemicellulose , Cellulase , Biomass conversion , Biomass energy -- South Africa , Energy crops -- South Africa , Bagasse -- Biodegradation , Pineapple -- Biodegradation
Description: The cellulosome is a multimeric enzyme complex that has the ability to metabolise a wide variety of carbonaceous compounds. Cellulosomal composition may vary according to the microbe’s nutritional requirement and allows for the anaerobic degradation of complex substrates. The complex substrates of interest in this research study were sugarcane bagasse and pineapple fibre waste, as they represent two important lignocellulosic, South African agricultural crops. The effective degradation of complex plant biomass wastes may present a valuable source of renewable compounds for the production of a variety of biofuels, for example bioethanol, and a variety of biocomposites of industrial importance. The identification of renewable energy sources for the production of biofuels is becoming increasingly important, as a result of the rapid depletion of the fossil fuels that are traditionally used as energy sources. An effective means of completely degrading lignocellulose biomass still remains elusive due to the complex heterogeneity of the substrate structure, and the fact that the effective degradation of the substrate requires a consortium of enzymes. The cellulosome not only provides a variety of enzymes with varying specificities, but also promote a close proximity between the catalytic components (enzymes). The close proximity between the enzymes promotes the synergistic degradation of complex plant biomass for the production of valuable energy products. Previous synergy studies have focused predominantly on the synergistic associations between cellulases; however, the synergy between hemicellulases has occasionally been documented. This research project established the synergistic associations between two Clostridium cellulovorans hemicellulases that may be incorporated into the cellulosome and a cellulosomal endoglucanase that is conserved in all cellulosomes. This research study indicated that there was indeed a synergistic degradation of the complex plant biomass (sugarcane bagasse and pineapple fibre). The degrees of synergy and the ratio of the enzymes varied between the two complex substrates. The initial degradation of the bagasse required the presence of all the enzymes and proceeded at an enhanced rate under sulphidogenic conditions; however, there was a low production of fermentable sugars. The low quantity of fermentable sugars produced by the degradation of the bagasse may be related to the chemical composition of the substrate. The sugarcane contains a high percentage of lignin forming a protective layer around the holocellulose, thus the glycosidic bonds are shielded extensively from enzymatic attack. In comparison, the initial degradation of the pineapple fibre required the action of hemicellulases, and proceeded at an enhanced rate under sulphidogenic conditions. The initial degradation of the pineapple fibre produced a substantially larger quantity of fermentable sugars in comparison to the bagasse. The higher production of fermentable sugars from the degradation of the pineapple fibre may be explained by the fact that this substrate may have a lower percentage of lignin than the bagasse, thus allowing a larger percentage of the glycosidic bonds to be exposed to enzymatic attack. The data obtained also indicated that the glycosidic bonds from the hemicellulosic components of the pineapple fibre shielded the glycosidic bonds of the cellulose component. The identification of the chemical components of the different substrates may allow for the initial development of an ideal enzyme complex (designer cellulosome) with enzymes in an ideal ratio with optimal synergy that will effectively degrade the complex plant biomass substrate.
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Date Issued: 2008

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Creating a virtual classroom: evaluating the use of online discussion forums to increase teaching and learning activities in an introductory accounting class

- Bezuidenhout, L Peta

Authors: Bezuidenhout, L Peta
Date: 2008
Language: English
Type: Conference paper
Identifier: vital:6082 , http://hdl.handle.net/10962/d1008586
Description: In teaching large classes, the educationally beneficial informal interaction between students and between lecturer and students is generally reduced, while effective use of both students' and lecturer's time is often a challenge. During student consultations, especially over the already stressful test and examination periods, many of the questions asked by the students are the same or similar. The lecturer needs to respond to each query by providing the same detailed explanation for the problem, resulting in ineffective use of time for the lecturer, while students waste time waiting for an appointment, or more often, simply don't bother to follow up on any queries they may have. Having a social presence is important for students' cognitive development, but in a large class posing questions or interrogating issues during a lecture appears to be challenging for many students. It is often not easy for students to initiate discussions or establish relationships with peers or the lecturer due to feelings of vulnerability and due to the size and impersonal atmosphere of the lecture theatre. This paper deals with the introduction of online discussion forums in an introductory accounting course and the benefits and problems experienced by the students, tutors and lecturer as a result thereof. Feedback received from these participants is discussed. The introduction and use of these forums resulted in a virtual classroom being created, where significantly more teaching and learning activities took place, to the benefit of all participants. Participation could have been peripheral - in the form of simply reading discussions; or active – through posting questions, or responding to questions.
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Date Issued: 2008

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Creating a virtual classroom: evaluating the use of online discussion forums to increase teaching and learning activities in an introductory accounting class

- Bezuidenhout, L Peta

Authors: Bezuidenhout, L Peta
Date: 2008
Subjects: To be catalogued
Language: English
Type: Conference paper
Identifier: vital:6069 , http://hdl.handle.net/10962/d1004630
Description: In teaching large classes, the educationally beneficial informal interaction between students and between lecturer and students is generally reduced, while effective use of both students' and lecturer's time is often a challenge. During student consultations, especially over the already stressful test and examination periods, many of the questions asked by the students are the same or similar. The lecturer needs to respond to each query by providing the same detailed explanation for the problem, resulting in ineffective use of time for the lecturer, while students waste time waiting for an appointment, or more often, simply don't bother to follow up on any queries they may have. Having a social presence is important for students' cognitive development, but in a large class posing questions or interrogating issues during a lecture appears to be challenging for many students. It is often not easy for students to initiate discussions or establish relationships with peers or the lecturer due to feelings of vulnerability and due to the size and impersonal atmosphere of the lecture theatre. This paper deals with the introduction of online discussion forums in an introductory accounting course and the benefits and problems experienced by the students, tutors and lecturer as a result thereof. Feedback received from these participants is discussed. The introduction and use of these forums resulted in a virtual classroom being created, where significantly more teaching and learning activities took place, to the benefit of all participants. Participation could have been peripheral - in the form of simply reading discussions; or active – through posting questions, or responding to questions.
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Date Issued: 2008

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Using assessment and reflexive teaching practices to inform and guide changes to the teaching and learning activities in Introductory Accounting

- Bezuidenhout, L Peta

Authors: Bezuidenhout, L Peta
Date: 2008
Language: English
Type: Conference paper
Identifier: vital:6081 , http://hdl.handle.net/10962/d1008585
Description: Teaching accounting to first year university students in higher education institutions is becoming increasingly complex as we deal with increasing class sizes, increasing diversity and a student body which appears to be less inclined to study without external motivating factors, while to be successful in studying accounting requires more than passive learning. Our aim was to make our students active participants in their accounting studies. After studying established research into assessment and approaches to student learning, changes were made to our course to ensure increased and active participation from our students. Critical to this change was guiding students in making the shift from a surface approach to learning, to a deep approach to learning where they would engage with the subject matter in a manner more likely to result in truly understanding the concepts and principles being taught. An important part of implementing these changes was asking our students to evaluate the innovations after they had taken place. Feedback received from our students resulted in the use of a new and unplanned innovation in the form of the setting of regular mini-tests. This was arguably the most successful of all the interventions introduced during the year and resulted in our journey being more exciting and less predictable than expected.
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Date Issued: 2008

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Using assessment and reflexive teaching practices to inform and guide changes to the teaching and learning activities in Introductory Accounting

- Bezuidenhout, L Peta

Authors: Bezuidenhout, L Peta
Date: 2008
Subjects: To be catalogued
Language: English
Type: Conference paper
Identifier: vital:6068 , http://hdl.handle.net/10962/d1004622
Description: Teaching accounting to first year university students in higher education institutions is becoming increasingly complex as we deal with increasing class sizes, increasing diversity and a student body which appears to be less inclined to study without external motivating factors, while to be successful in studying accounting requires more than passive learning. Our aim was to make our students active participants in their accounting studies. After studying established research into assessment and approaches to student learning, changes were made to our course to ensure increased and active participation from our students. Critical to this change was guiding students in making the shift from a surface approach to learning, to a deep approach to learning where they would engage with the subject matter in a manner more likely to result in truly understanding the concepts and principles being taught. An important part of implementing these changes was asking our students to evaluate the innovations after they had taken place. Feedback received from our students resulted in the use of a new and unplanned innovation in the form of the setting of regular mini-tests. This was arguably the most successful of all the interventions introduced during the year and resulted in our journey being more exciting and less predictable than expected.
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Date Issued: 2008

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Ray Charles: a psychobiographical study

- Biggs, Ilze

Authors: Biggs, Ilze
Date: 2008
Subjects: Charles, Ray, 1930-2004 Psychology -- Biographical methods -- Case studies Jazz singers -- Biography Blind entertainers -- Psychology
Language: English
Type: Thesis , Masters , MA
Identifier: vital:2933 , http://hdl.handle.net/10962/d1002442
Description: Psychobiography is the formulation of an individual's narrative according to a psychological theory. Psychobiographical researchers face a number of challenges. One pertinent challenge is the limited amount of psychobiographical research conducted at academic institutions, including South Africa. Although a number of studies had been completed in the past decade, the impact of psychobiographical research remains negligible. Although much has been written about Ray Charles, none of the existing literature adopted a specific psychological focus. Charles developed from a young boy in a poverty stricken, racially segregated society into an exceptionally successful musician who worked productively until he died at the age of 73. He was selected as the subject on the basis of interest value, uniqueness and significance of life achievements. The primary aim of this study was to explore and describe the development of Charles according to Levinson's (Levinson, et. ai, 1978) theoretical framework. Levinson's theory of adult development identifies and describes the important changes that occur throughout the lifespan of an individual. A secondary aim was to provide an understanding of Charles within the social, economic and historical context in which he lived. The data collection and analysis was conducted according to Yin's (2003) 'analytic generalization'. The data was analysed according to three linked sub-processes proposed by Huberman and Miles (1994).
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Date Issued: 2008

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The application of section 197 of the Labour Relations Act in an outsourcing context

- Biggs, Lynn

Authors: Biggs, Lynn
Date: 2008
Subjects: South Africa. Labour Relations Act (1995) , Labor laws and legislation -- South Africa , Contracting out -- Law and legislation -- South Africa
Language: English
Type: Thesis , Masters , LLM
Identifier: vital:10193 , http://hdl.handle.net/10948/751 , South Africa. Labour Relations Act (1995) , Labor laws and legislation -- South Africa , Contracting out -- Law and legislation -- South Africa
Description: Section 197 of the Labour Relations Act (LRA) in both its original form and in its current form caused much confusion and debate. Originally it was interpreted that section 197 allowed for the automatic transfer of employees in cases where there was a transfer of the whole or part of a business, trade or undertaking as a going concern. That meant that the contracts of employment transfer to the new owner and that the employees could not refuse to be transferred. Various judges were tasked with interpreting this section in its original form and thus different interpretations emerged with the Labour Appeal Court ultimately deciding in the NEHAWU v University of Cape Town matter that employers involved in the transfer can decide between them, not to transfer the employees. The LAC further held that “outsourcing” does not necessarily entail a transfer of a business. Section 197 was amended in 2002 and the effect of the provisions is that the old employer is not required to seek the consent of the employees before their contracts are transferred and that the employment contracts transfer automatically. However, the current section has also raised some difficulties especially relating to: when does a transfer of a business as a going concern take place; what constitutes a “business”; when is an entity part of a business, trade, undertaking or service? A more glaring controversy relates to whether section 197 applies to “second-generation contracting out or outsourcing”. All provisions of the LRA should be interpreted in the context to advance economic development, social justice, labour peace and democratisation of the workplace. One of the primary objects of the LRA is to give effect to and to regulate the fundamental rights of the Constitution of the Republic of South Africa, 1996. Thus section 197 is to be interpreted in light of the objectives of the LRA as well as to promote the spirit, purport and objects of the Bill of Rights. The common law and international law are both important sources of comparison. The common law allows employers who transfer businesses free to decide whether or not the transfer will include the employees of the transferor. International law, particularly the European Union and the United Kingdom, favour the approach that when an entity is transferred, it retains its identity after the transfer and the safeguarding of employee rights in the context of business transfers. European and English jurisprudence have shown that almost any combination of events can constitute a transfer of a business.
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Date Issued: 2008

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Pan-African multilateralism: transformative or disconnected?

- Bischoff, Paul, 1954-

Authors: Bischoff, Paul, 1954-
Date: 2008
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/161452 , vital:40628 , https://doi.org/10.1080/02589340802366968
Description: Despite a multitude of international institutions on the African continent, worldwide Africa's multilateralism has generally received little attention. Yet, with the emergence of the African Union (AU) and its institutions, questions arise about its character. Will rhetoric and state symbolism take the place of substance or will the space opened up for democracy and civil society participation allow for greater democratically informed sustainability? With this in mind, the article addresses the issue to what extent the character of African multilateralism continues to display features of disconnectedness as opposed to those of transformation, where its institutions address issues of uneven development in concert with civil society concerns.
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Date Issued: 2008

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The feeding and spatial ecologies of the large carnivore guild on Kwandwe Private Game Reserve

- Bissett, Charlene

Authors: Bissett, Charlene
Date: 2008
Subjects: Wildlife conservation -- South Africa -- Eastern Cape Kwandwe Private Game Reserve Lion -- Behavior -- South Africa -- Eastern Cape Lion -- Nutrition -- South Africa -- Eastern Cape Cheetah -- Behavior -- South Africa -- Eastern Cape Cheetah -- Nutrition -- South Africa -- Eastern Cape African wild dog -- South Africa -- Eastern Cape Spatial behavior in animals Predation (Biology) Game reserves -- Management
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:5802 , http://hdl.handle.net/10962/d1006195
Description: The reintroduction of lions, cheetahs and African wild dogs to Kwandwe Private Game Reserve in the Eastern Cape Province of South Africa created the opportunity to study the biology and behaviour of these large carnivores in an enclosed system. The research focused on space utilisation and feeding ecology of the predators, using standard observational methods. Changes in the structure of the carnivore guild, and changes in the prey base that occurred during the study were used as natural experiments to examine factors affecting space use and diet. In general, the diets of the predators were similar to previous studies and prey abundance was more important than prey species size in determining prey selection. Changes in the abundance of certain prey species was matched by a dietary switch in lions from kudu to warthog and an increase in the proportion of springbok kills by the cheetahs. There was no significant difference in the proportions of prey species detected by ad hoc or continuous observations. Core areas occupied by the predators were significantly smaller than home ranges except when females were denning. Home ranges overlapped both within and between species, but there was very little overlap of core areas. An increase in the number of lion prides in the area during the study resulted in an increase in overlap of home ranges of lions and cheetahs, but did not result in a change in home range size. Space use by female cheetahs with cubs increased as the cubs grew older. The use of thicket vegetation by cheetahs decreased with an increase in the number of lion prides. Minimum Daily Energy Expenditure, energy intake and net benefit were calculated for the predators using data from continuous observations. All predators exhibited a large net benefit and the net benefit for single female cheetahs was greater than for the members of the coalition. Net benefit for the alpha pair of African wild dogs was lower than that of the pack.
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Date Issued: 2008

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The antecedents of customer satisfaction in a financial institution : a qualitative study

- Bleske, Adrian

Authors: Bleske, Adrian
Date: 2008
Subjects: Standard Bank Properties , Banks and banking -- South Africa , Banks and banking -- Customer services -- South Africa , Financial services industry -- South Africa , Bank management -- South Africa , Banks and banking -- Customer services -- Effect of marketing on
Language: English
Type: Thesis , Masters , MBA
Identifier: vital:840 , http://hdl.handle.net/10962/d1015482
Description: The following is a case study report on the Cape Town business unit of Standard Bank Properties. The research project falls within the ambit of services marketing which introduces several unique management challenges for service businesses that sell services as a core offering. The principal aim of the case study is to gain an understanding of why customers bank at the business unit and to discover what aspects are critical to customer satisfaction. A further goal of the research is to examine how the business unit could improve customer satisfaction and to highlight any impediments to further improving customer satisfaction at the business unit. It is generally regarded that quality customer service is essential to building customer relationships and hence the research project emphasis on services marketing and customer satisfaction within a financial services context. The paper commences with an overview of the South African Banking Sector and its unique challenges such as the Financial Service Charter and newly introduced legislation such as Financial Intelligence Centre Act. The case study will specifically investigate the property finance industry and a detailed analysis of the business unit's operations and process flow will also be undertaken. The reason for this background information is to assist the reader to understand how the business unit operates. The research project will investigate four unique differences between goods marketing and services marketing whereafter three theoretical propositions are introduced, namely the dyadic interaction and service encounter, the Service Profit Chain and finally Relationship Marketing. Evidence in the form of a narrative will be led from insights obtained from interviews conducted with customers and staff at the business unit against these propositions with support (or otherwise) from independent surveys and documents from the business unit. The result of this analysis is the identification of several areas of concern specifically: New employees and the service encounter, Problems with FICA, Lack of a customer complaint handling system, Empowerment issues, Turnaround times, Reliance on key staff These insights together with the evidence from the literature review will be analysed and several recommendations made to improve customer service and ultimately customer satisfaction at the business unit. Several recommendations for further research are offered as well as the identification of limitations including but not limited to the specificity of the case study report.
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Date Issued: 2008

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Enigmatic trace fossils from the Aeolian lower Jurassic Clarens formation, Southern Africa

- Bordy, Emese M

Authors: Bordy, Emese M
Date: 2008
Language: English
Type: Article
Identifier: vital:6730 , http://hdl.handle.net/10962/d1007538
Description: The Lower Jurassic aeolienites of the Clarens Formation in southern Africa contain unique sedimentary structures that are unlikely to be non-biogenic. They are also unlike any known modern or ancient trace fossils. Here, some nigmatic, horizontal,regularly-oriented sedimentary structures are described, which occur in association with other trace fossils as well as features that were previously nterpreted as nests of termites or termite-like ancient social nsects. These spectacular structures are exposed in enormous profusion as straight, ~5 mm cylinders with strong compass orientation, in parallel alignment with one another and to ancient horizontal bedding planes. Their fill is identical to that of the host rock: clean, well-sorted, very fine- to finegrained quartz-arenite. In cross-section, each structure is defined by a subtle, ~0.1 mm thin, concentric gap. Without comparable modern biogenic structures, the biological origin of the structures is uncertain. Their strong compass orientations are, however, also inconsistent with an inorganic origin, even though they may resemble pipey concretions generated by flowing groundwater. Nonetheless, this paper, based on spatiotemporal distribution patterns of the oriented structures, their locally high abundance and association with obvious trace fossils, as well as other sedimentological and palaeontological lines of evidence, argues that the compass structures may be products of ancient social invertebrates living in a resource-limited, semi-arid to arid environment. Furthermore, the compass structures as well as the accompanying structures of the predominantly aeolian Clarens Formation collectively imply the recurrence of favourable ecological parameters (e.g., moist ubstrates) related to episodic climate fluctuations in the Early Jurassic of southern Pangaea (i.e., southern Gondwana).
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Date Issued: 2008

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Engendering childhood: concerning the content of South African Television content

- Boshoff, Priscilla A, Prinsloo, Jeanne

Authors: Boshoff, Priscilla A , Prinsloo, Jeanne
Date: 2008
Language: English
Type: text , book
Identifier: http://hdl.handle.net/10962/143560 , vital:38257 , ISBN , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
Description: The essays in this volume reflect a wide-range of issues and concerns related to children’s media culture in Africa. For example, several address the role of entertainment television in Addis Abba, Ghana, South Africa, Kenya, and Zambia and in the lives of Muslim children. Other essays introduce us to children-centered media from Ghana, South Africa, and Zimbabwe, and the innovative programs of PLAN-International. In addition to entertainment media and children-centered media, media education and digital media literacy are also discussed.
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Date Issued: 2008

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An assessment of information systems supporting procurement reforms in the Eastern Cape provincial government

- Bosire, Samuel Mobisa

Authors: Bosire, Samuel Mobisa
Date: 2008
Subjects: Government purchasing -- South Africa -- Eastern Cape , Public finance -- South Africa -- Eastern Cape
Language: English
Type: Thesis , Masters , MPA
Identifier: vital:11620 , http://hdl.handle.net/10353/214 , Government purchasing -- South Africa -- Eastern Cape , Public finance -- South Africa -- Eastern Cape
Description: As part of the on going financial management reforms, the South African Government introduced the Supply Chain Management (SCM) Framework. Since 2004, The Eastern Cape Provincial Government embarked on a process of ensuring that procurement reforms wrought by the advent of SCM are seamlessly ushered in. Information Technology (IT) and systems are a sine qua non in supporting the implementation of the SCM Framework. However, IT does not operate in a vacuum. Many other factors complement, supplement and influence the objectives sought through the use of Information Technology and systems. It is the confluence of this factors that eventually will determine that success or failure of using technology to support procurement reforms in government. The research investigates the factors affecting the success of the Information systems underlying SCM in the Eastern Cape Provincial government. Data for the research was gathered using a questionnaire administered to all Eastern Cape Provincial Government departments. The research borrows from Heeks’ ITPOSMO model in assessing SCM and Information Systems structures and processes and gauging their state of readiness to embrace procurement reforms envisaged through the SCM Framework. Because of the importance of having a strong IT functional unit in any government department, the study highlights IT issues that typically confront IT managers, especially in the public sector. Heeks’ ITPOSMO model emerges as a sufficient framework for identifying gaps that currently exist between the reality and perceptions on the readiness of IT to adequately support government procurement reforms. The dissertation concludes that the success of the system is dependent not only on the technological component of the system, but also on other factors.
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Date Issued: 2008

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A xylem retrieval pathway in rice leaf blades – evidence of a role for endocytosis?

- Botha, Christiaan E J, Aoki, N, Scofield, G N, Liu, Lin, Furbank, R T, White, R G

Authors: Botha, Christiaan E J , Aoki, N , Scofield, G N , Liu, Lin , Furbank, R T , White, R G
Date: 2008
Language: English
Type: Article
Identifier: vital:6505 , http://hdl.handle.net/10962/d1005930 , http://dx.doi.org/10.1093/jxb/ern150
Description: The structure and transport properties of pit membranes at the interface between the metaxylem and xylem parenchyma cells and the possible role of these pit membranes in solute transfer to the phloem was investigated. Electron microscopy revealed a fibrillar, almost tubular matrix within the pit membrane structure between the xylem vessels and xylem parenchyma of leaf blade bundles in rice (Oryza sativa). These pits are involved primarily with regulating water flux to the surrounding xylem parenchyma cells. Vascular parenchyma cells contain large mitochondrial populations, numerous dictyosomes, endomembrane complexes and vesicles in close proximity to the pit membrane. Taken collectively this suggests that endocytosis may occur at this interface. A weak solution of 5,6-carboxyfluorescein diacetate (5,6-CFDA) was applied to cut ends of leaves and after a minimum of 45 minutes, the distribution of the fluorescent cleavage product, 5,6-carboxyfluorescein (5,6-CF) was observed using confocal microscopy. Cleavage of 5,6-CFDA occurred within the xylem parenchyma cells and the non-polar 5,6-CF was then symplasmically transported to other parenchyma elements and ultimately, via numerous pore plasmodesmata, to adjacent thick-walled sieve tubes. Application of Lucifer Yellow, and, separately, Texas Red labelled dextran (10 kDa) to the transpiration stream, confirmed that these membrane-impermeant probes could only have been offloaded from the xylem via the xylem vessel-xylem parenchyma pit membranes, suggesting endocytotic transmembrane transfer of these membrane-impermeant fluorophores. Accumulation within the thick-walled sieve tubes, but not in thin-walled sieve tubes, confirms the presence of a symplasmic phloem loading pathway, via pore plasmodesmata between xylem parenchyma and thick-walled sieve tubes, but not thin-walled sieve tubes.
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Date Issued: 2008

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Towards the development of InAs/GaInSb strained-layer superlattices for infrared detection

- Botha, Lindsay

Authors: Botha, Lindsay
Date: 2008
Subjects: Gallium arsenide semiconductors , Indium alloys , Compound semiconductors , Organometallic compounds , Infrared detectors , Infrared technology , Superlattices as materials
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:10526 , http://hdl.handle.net/10948/713 , Gallium arsenide semiconductors , Indium alloys , Compound semiconductors , Organometallic compounds , Infrared detectors , Infrared technology , Superlattices as materials
Description: This study focuses on the development of InAs/GaInSb strained-layer superlattice structures by metal organic chemical vapour deposition (MOCVD), and deals with two aspects of the development of InAs/GaInSb SLS’s by MOCVD viz. the deposition of nano-scale (~100 Å) GaInSb layers, and the electrical characterization of unstrained InAs. The first part of this work aims to study the MOCVD growth of GaInSb layers in terms of deposition rate and indium incorporation on the nano-scale. This task is approached by first optimizing the growth of relatively thick (~2 μm) epitaxial films, and then assuming similar growth parameters during nano-scale deposition. The GaInSb layers were grown as part of GaInSb/GaSb quantum well (QW) structures. By using this approach, the GaInSb QW’s (~100 Å) could be characterized with the use of photoluminescence spectroscopy, which, when used in conjunction with transmission electron microscopy and/or X-ray diffractomery, proves useful in the analysis of such small scale deposition. It is shown that the growth rate of GaInSb on the nano-scale approaches the nominal growth rates determined from thick (~2 μm) GaInSb calibration layers. The In incorporation efficiency in nano-layers, however, was markedly lower than what was predicted by the GaInSb calibration layers. This reduction in indium incorporation could be the result of the effects of strain on In incorporation. The choice of substrate orientation for QW deposition was also studied. QW structures were grown simultaneously on both (100) and 2°off (100) GaSb(Te) substrates, and it is shown that growth on non-vicinal substrates is more conducive to the deposition of high quality QW structures. The second part of this study focuses on the electrical characterization of unstrained InAs. It is long known that conventional Hall measurements cannot be used to accurately characterize InAs epitaxial layers, as a result of parallel conduction resulting from surface and/or interface effects. This study looks at extracting the surface and bulk electrical properties of n-type InAs thin films directly from variable magnetic field Hall measurements. For p-type InAs, the situation is complicated by the relatively large electron to hole mobility ratio of InAs which tends to conceal the p-type nature of InAs thin films from Hall measurements. Here, this effect is illustrated by way of theoretical simulation of Hall data.
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Date Issued: 2008

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Experiences and coping resources of the suicide negotiation staff at the Van Staden's Bridge

- Botha, Miranda

Authors: Botha, Miranda
Date: 2008
Subjects: Adjustment (Psychology) , Negotiation , Suicide -- Prevention
Language: English
Type: Thesis , Masters , MA
Identifier: vital:9926 , http://hdl.handle.net/10948/656 , Adjustment (Psychology) , Negotiation , Suicide -- Prevention
Description: The Van Staden’s Bridge has claimed 67 lives since its construction on 11 November 1971. A team of police officials, trained as negotiators who deal with suicide and hostage negotiation, are involved with the task of convincing suicidal persons who turn to the bridge to take their own lives, not to resort to suicide. They are responsible for persuading at least three people per week to reconisider suicide at this notorious bridge. The goal of this study was to explore and describe the experiences and coping resources of the SAPS suicide negotiation staff at the Van Staden’s Bridge, Thornhill, Port Elizabeth. A mixed methods study combining both the quantitative and qualitative approaches was implemented. An exploratory-descriptive design was used, because the topic is still a relatively under-researched area in South Africa. Two data collection measures, that is, the Coping Resources Inventory (CRI) and semi-structured interviewing were employed. The researcher conducted a pilot study to enhance the trustworthiness of the study. Non-probability, purposive sampling was employed to obtain research participants from the research population (suicide negotiation team), consisting of 12 members. Eight members participated voluntary in the quantitative data collection and of these a total of five participated in the qualitative research interviews. Six themes emerged from the results of the in-depth, semi-structured interviews: (1) experiences of SAPS suicide negotiators, (2) aspects that hinder the negotiation process, (3) characteristics of a negotiator, (4) important aspects of the negotiation process, (5) coping mechanisms of SAPS negotiators and (6) recommendations for rendering support to SAPS negotiators. The results from the CRI suggested that the participants have average coping resources with the cognitive domain being the lowest and both the social and physical domains being the highest. The limitations and the value of the study were outlined and finally, recommendations for future research were made.
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Date Issued: 2008

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The Southern African Development Community's attraction to foreign direct investment

- Botha, Richard Kruger

Authors: Botha, Richard Kruger
Date: 2008
Subjects: Southern African Development Community , Africa, Southern -- Foreign economic relations , Africa, Southern -- Economic integration , Africa, Southern -- Economic conditions
Language: English
Type: Thesis , Masters , MBA
Identifier: vital:8716 , http://hdl.handle.net/10948/926 , Southern African Development Community , Africa, Southern -- Foreign economic relations , Africa, Southern -- Economic integration , Africa, Southern -- Economic conditions
Description: In order to assess the question as to whether the Southern African Development Community in principle attracts foreign direct investment, literature and data have been cited that compared the economic profiles and relative privatisation programs of member states of the Southern African Development Community with relative high inflows of foreign direct investment with the economic profiles and relative privatisation programs of member states with relative low inflows of foreign direct investment. Qualitative research has been conducted, and the author is of opinion that generally the member states with relative high foreign direct investment inflows had economic profiles and relative privatisation programs that encouraged foreign direct investment, and member states with relative low foreign direct investment inflows had economic profiles and relative privatisation programs that deterred foreign direct investment inflows. From the above the author has inferred that the Southern African Development Community in principle attracted foreign direct investment, but not to its full potential. The reason may be that although the member states’ economic profiles are favourable for foreign direct investment, their economic growths tend to fluctuate, and the future economic profiles are therefore unpredictable. With the above in mind this mini-treatise aims to address the question as to what steps the governments of the Southern African Development Community’s member states could follow in order to attract foreign direct investment. iii The author is of opinion that the member states should endeavour to maintain an annual average economic growth rate, and that the governments continue to engage into privatisation programs in order to encourage foreign direct investment.
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Date Issued: 2008

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