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Celebrating libraries in 20 years of democracy: An overview of library and information services in South Africa
No full textOriginal publication is available at: http://dx.doi.org/10.1177/0340035215585100Since the establishment of the first public library in 1818, the South African library and information services
landscape has also been a reflection of the socio-political order and developments in the country. This
article presents an historical perspective as well as an overview of libraries in South Africa since 1994, the
context within which libraries function, library governance and legislative framework, government funding
for redress, library technologies, library and information services education and the professional
association. The article further highlights the importance of libraries in meeting the goals of the national
development agenda towards entrenching a strong democracy and an educated and informed natio
Towards large scale software based network routing simulation
No full textSoftware based routing simulators suffer from large simulation host requirements and
are prone to slow downs because of resource limitations, as well as context switching
due to user space to kernel space requests. Furthermore, hardware based simulations
do not scale with the passing of time as their available resources are set at the time of
manufacture.
This research aims to provide a software based, scalable solution to network simulation.
It aims to achieve this by a Linux kernel-based solution, through insertion of a custom
kernel module. This will reduce the number of context switches by eliminating the user
space context requirement, and serve to be highly compatible with any host that can run
the Linux kernel.
Through careful consideration in data structure choice and software component design,
this routing simulator achieved results of over 7 Gbps of throughput over multiple simulated
node hops on consumer hardware. Alongside this throughput, this routing simulator
also brings to light scalability and the ability to instantiate and simulate networks in
excess of 1 million routing nodes within 1 GB of system memor
Towards a framework for building security operation centers
No full textIn this thesis a framework for Security Operation Centers (SOCs) is proposed. It was developed by utilising Systems Engineering best practices, combined with industry-accepted standards and frameworks, such as the TM Forum’s eTOM framework, CoBIT, ITIL, and ISO/IEC 27002:2005.
This framework encompasses the design considerations, the operational considerations and the means to measure the effectiveness and efficiency of SOCs. The intent is to provide guidance to consumers on how to compare and measure the capabilities of SOCs provided by disparate service providers, and to provide service providers (internal and external) a framework to use when building and improving their offerings.
The importance of providing a consistent, measureable and guaranteed service to customers is becoming more important, as there is an increased focus on holistic management of security. This has in turn resulted in an increased number of both internal and managed service provider solutions.
While some frameworks exist for designing, building and operating specific security technologies used within SOCs, we did not find any comprehensive framework for designing, building and managing SOCs. Consequently, consumers of SOCs do not enjoy a constant experience from vendors, and may experience inconsistent services from geographically dispersed offerings provided by the same vendor
Analysis of predictive power of binding affinity of PBM-derived sequences
No full textA transcription factor (TF) is a protein that binds to specific DNA sequences as part of the initiation stage of transcription. Various methods of finding these transcription factor binding sites (TFBS) have been developed. In vivo technologies analyze DNA binding regions known to have bound to a TF in a living cell. Most widely used in vivo methods at the moment are chromatin immunoprecipitation followed by deep sequencing (ChIP-seq) and DNase I hypersensitive sites sequencing. In vitro methods derive TFBS based on experiments with TFs and DNA usually in artificial settings or computationally. An example is the Protein Binding Microarray which uses artificially constructed DNA sequences to determine the short sequences that are most likely to bind to a TF. The major drawback of this approach is that binding of TFs in vivo is also dependent on other factors such as chromatin accessibility and the presence of cofactors. Therefore TFBS derived from the PBM technique might not resemble the true DNA binding sequences.
In this work, we use PBM data from the UniPROBE motif database, ChIP-seq data and DNase I hypersensitive sites data. Using the Spearman’s rank correlation and area under receiver operating characteristic curve, we compare the enrichment scores which the PBM approach assigns to its identified sequences and the frequency of these sequences in likely binding regions and the human genome as a whole. We also use central motif enrichment analysis (CentriMo) to compare the enrichment of UniPROBE motifs with in vivo derived motifs (from the JASPAR CORE database) in their respective TF ChIP-seq peak region. CentriMo is applied to 14 TF ChIP-seq peak regions from different cell lines. We aim to establish if there is a relationship between the occurrences of UniPROBE 8-mer patterns in likely binding regions and their enrichment score and how well the in vitro derived motifs match in vivo binding specificity.
We did not come out with a particular trend showing failure of the PBM approach to predict in vivo binding specificity. Our results show Ets1, Hnf4a and Tcf3 show prediction failure by the PBM technique in terms of our Spearman’s rank correlation for ChIP-seq data and central motif enrichment analysis. However, the PBM technique also matched the in vivo binding specificities of FoxA2, Pou2f2 and Mafk. Failure of the PBM approach was found to be a result of variability in the TF’s binding specificity, the presence of cofactors, narrow binding specificity and the presence ubiquitous binding patterns
Female identity in the post-millennial Nigerian novel: a study of Adichie, Atta, and Unigwe
No full textThis thesis project examines the work of three female Nigerian authors: Chimamanda Ngozi Adichie, Sefi Atta and Chika Unigwe. They are part of a growing number of young African writers who are receiving international acclaim and challenging narratives that have long defined the continent in pejorative terms. They question what it means to be female and African in a transcultural, global world but counter discourses that are both restrictive and prescriptive. Their female characters are not imaged in binary terms as either victims or villains. For all three writers, the African story has to be told in its entirety incorporating what some may argue are negative stereotypes but doing so in a manner that examines and undermines those same stereotypes. For the purposes of the thesis, I focus on their first novels: Adichie’s Purple Hibiscus, Atta’s Everything Good Will Come and Unigwe’s On Black Sisters’ Street. Chapter One examines Purple Hibiscus and argues that the novel is much more than a coming of age story or, as some critics have posited, an allegory of the postcolonial state. Chapter Two highlights Atta’s use of fairly familiar feminist theories but grounds them in the lived realities of the African city. All three authors are concerned with issues of violence and death. Unigwe’s novel, which forms the focus of Chapter Three, offers a critical perspective on how both of those themes intersect with the increasing commercialisation of global culture. Her characters are female sex workers whose lives are irrevocably altered by the murder of one of their colleagues. I conclude by arguing that the three novels offer a nuanced if not necessarily new understanding of the various social, economic and political forces that continue to shape the lives of women on the continent
The cheetahs of the Northern Tuli Game Reserve, Botswana : population estimates, monitoring techniques and human-predator conflict
No full textRemaining viable cheetah (Acinonyx jubatus) populations in Africa are threatened by direct
persecution through conflict with farmers and habitat degradation and fragmentation.
Botswana is considered a stronghold for free roaming cheetahs in Africa, yet the country has
had relatively limited research on its cheetahs, and information from the east of the country is
lacking. Data on the current status of populations is thus required to make informed
management decisions. My study provides estimates of population density, abundance,
distribution and status for the demographically open cheetah population of the Northern Tuli
Game Reserve (NOTUGRE) in Botswana. The effectiveness of two population monitoring
methods, namely camera trapping and a photographic survey, were also investigated.
Moreover, I report on the level of conflict between livestock farmers and predators on rural
communal farmlands within and adjacent to NOTUGRE. Data were collected between May
2012 and November 2013. Results indicate a low population density of 0.61 ± 0.18 adult
cheetahs per 100 km² and a minimum population size of 10 individuals (nine adults and one
cub). Camera traps placed at cheetah scent-marking posts increased detection rates and
provided ideal set up locations. This approach, together with Spatial Explicit Capture-
Recapture (SECR) models, is recommended for future studies. The long-term studies that are
required to better understand the status of cheetahs in Botswana do not exist. Thus,
photographic surveys may provide an alternative method for providing baseline data on
population numbers, distribution and demography. The third aspect of my study gathered
information on levels of livestock loss and human tolerance of predators through the use of
interviews (n = 80). Conflict with subsistence farmers is a concern as livestock depredation is
relatively high (9.1% of total livestock owned) and farmers had an overall negative attitude
towards conservation of large predators. My results suggest that human-predator conflict in
this area is more complex than the direct financial loss from depredation. Hence, reducingdepredation rates alone is unlikely to change farmer tolerance of wildlife on farmlands.
Improved, responsible farm management, including self-responsibility for livestock rearing,
and positive appreciation for wildlife are necessary. The NOTUGRE cheetah population
requires further research to understand possible threats to the population. Furthermore, a
better understanding of the connectivity between cheetahs of NOTUGRE, South Africa and
Zimbabwe is required. The number of cheetahs within NOTUGRE is too small to sustain a
viable population, hence conserving cheetahs outside of the protected area should be a
priority for the conservation of the population. This can only be achieved through assistance
and involvement from national authorities, local people and conservation organisations
An ergonomics intervention study into the physiological, perceptual and productivity effects of three citrus harvesting bag designs in the Eastern Cape of South Africa : a combined laboratory and field approach
No full textName on Graduation Programme: Bassey-Duke, Elizabeth MissanBackground: Agriculture plays a vital role in the economy of any industrially developing country, including South Africa. In the Eastern Cape of South Africa citrus farming is a significant contributor to the local economy (Johnson et al., 2005). The harvesting phase of citrus farming is performed manually and exposes workers to physical risks, which can lead to the development of musculoskeletal disorders. In particular, the standard harvesting bag comprises of a single shoulder strap and promotes asymmetrical load carriage which results in shoulder and lower back pain complaints. The current study compared the physiological (EMG), perceptual (RPE), usability (PUEU) and productivity effects of two new harvesting bag designs (a hip belt and a backpack bag design) to the standard harvesting bag design. This was performed in a laboratory as well as a field setting.
Methods (Laboratory phase): 36 participants (12 males and 24 females) were assigned to one worker group. The “tall ladder worker” group was comprised of only males and the “step ladder worker” and “ground worker” group of females. Each participant was required to simulate a citrus harvesting task while utilizing each of the bag designs on different days. On each day/test session, participants performed three harvesting cycles. Muscle activity was measured throughout the entire testing session and RPE were recorded at the end of each cycle.
Results (Laboratory phase): The EMG and RPE results indicate that the backpack design was the most ideal design to reduce asymmetry, while the standard harvesting bag design was the worst. Although not significant, there was greater muscle asymmetry (p=0.109) and a significantly higher perceived exertion when using the standard bag (p=0.0004), in comparison to using the backpack.
Methods (Field phase): 17 Xhosa-speaking citrus harvesters (6 females and 11 males) participated in this study. Each harvester worked with one of the three bag designs on a different day. Productivity of each worker was assessed every hour by recording the number of bags filled with fruit and at the end of the shift. A Perceived Usefulness & Ease of Use questionnaire was presented to each participant to obtain feedback on worker acceptance to the new bag designs.
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Results (Field phase): A general trend in support of the hip belt bag design over the other two bag designs were found, even within the different worker demographic groups (age, sex and worker experience). The workers perceived less exertion (7.98 ± 1.86) and were more productive (9.90 ± 2.11 bags/hour) when using the hip belt design; they also found this bag the most useful (1.02 ± 0.09) and easy to use (1.07 ± 0.25). In contrast, the backpack bag design had significantly poorer responses when compared to the other two bag designs and this was evident in all the dependent variables assessed (RPE, productivity and PUEU).
Conclusion: The results from the laboratory phase supported the expectation that the backpack bag design reduces asymmetry and hence, is more suitable than the standard harvesting bag. However, results from the field show that the hip belt bag design was the most preferred and the backpack was the least preferred. Bao & Shahnavaz (1989) highlight the need for ergonomics researcher to convey laboratory findings into the field context. However, as shown by the current study, there are numerous challenges associated with field work, making it difficult for laboratory findings to be successfully conveyed to the field.
Limitations and Recommendations: For the laboratory phase of the project, no biomechanical and cardiovascular responses were assessed. However, for a holistic approach, these variables should be considered in future studies. Due to high variability from one harvesting cycle to another, more than three harvesting cycles should also be performed to accurately replicate the harvesting process as done in the field over extended durations of time. For the field phase, data should be collected from more than one citrus farm and thus a larger sample size could be obtained. This would improve the validity of the study. In addition to this, data should be collected for a full working day, especially if environmental conditions are not a hindrance, as well as for a whole season, since workloads vary, depending on the time of the harvesting season
Teacher leadership practice : a case study of a public primary school in a semi-urban area of the Otjozondjupa Region, central Namibia
No full textThe education system in Namibia was shaped by the policies located within the framework of the
apartheid ideology. Since it gained its independence in 1990, the government positioned
education at the top of the national priorities. Thus, there has been a growing realisation of the
importance of more democratic forms of leadership in the education system for the country to be
able to cater for a democratic society. Amongst others, teachers became active creators and
managers of the learning outcomes. In addition, teachers are regarded as agents of change and
the driving force for productive teaching and learning. Literature describes how the management
in schools has been redistributing authority and power so that a culture of teacher leadership in
school communities can grow. More importantly, school improvement depends more on the
active involvement of teacher leaders as it is realised that people in formal positions cannot do
everything. In this line this study investigated the understanding of teachers and members of
management of teacher leadership practice and it further identified the structural and cultural
factors which enabled and inhibited this practice in a primary school.
This study is a case study of a Primary school in a semi-urban area of Otjozondjupa Region, a
central part of Namibia. This study was conducted in the interpretive paradigm and it is a
qualitative case in nature, employing semi-structured interviews, observation and document
analysis. Triangulation over the data revealed that respondents have an understanding of the
concept and that all teachers are involved in leadership roles at school which are more strongly
found in the classroom and through involvement with other teachers. Teacher leadership roles at
the case study school also occur within the whole school with some limitations and also extend
beyond the school. Grant’s (2008) model of teacher leadership was used to analyse the data.
The study suggested some hindrances and supporting factors of teacher leadership. The findings
suggested that teacher leadership is understood at the case study school and that they experienced
factors that enabled and hindered this practice at different stages. Enabling factors included the
school structure, further studies and workshops attended, while teacher leadership is impeded by
teachers’ unwillingness to collaborate with others and the platoon system. The study
recommends future large scale studies, including at secondary schools, so that a broader sense of
teacher leadership may emerge
Structural and optical properties of alloyed quaternary CdSeTeS core and CdSeTeS/ZnS core–shell quantum dots
No full textSynthesis of fluorescent alloyed quantum dots (QDs) with unique optical properties suitable for a wide array of chemical, physical and biological applications is of research interest. In this work, highly luminescent and photostable alloyed quaternary CdSeTeS core QDs of two different sizes were fabricated via the organometallic hot-injection synthetic route. Characterization of the nanocrystals were performed using TEM, XRD, UV/vis and fluorescence spectrophotometric techniques. We have demonstrated in this work that the well fabricated alloyed quaternary CdSeTeS core QDs possess unique optical properties that are advantageous over conventional core/shell systems. Formation of the CdSeTeS/ZnS core/shell with the desired optical properties comes with a number of challenges, hence the advantages of the quaternary alloyed core over the core/shell QDs are (i) avoidance of the challenging process of determining the proper shell thickness which can provide the desired optical properties in the core/shell system and (ii) avoidance of the lattice-induced mismatch between the core and the shell material which can either lead to incomplete exciton confinement or dislocation at the core/shell interface.Original publication is available at http://dx.doi.org/10.1016/j.jallcom.2015.05.08