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Post laryngoplasty ultrasonography of the horse larynxMiller, Sean Myles January 2018 (has links)
* / Dissertation (MSc)--University of Pretoria, 2018. / Veterinary Science / MSc / Unrestricted
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A comparative proteomic and glycoproteomic study of platelets from patients with diabetes and non-diabetic healthy individualsMlambo, Shamiso Shelter January 2018 (has links)
Introduction: Diabetes mellitus is considered one of the four major non-communicable disease with the global prevalence of this disease nearly doubling over the past 40 years, making it one of the leading causes of morbidity and contributing to mortality.
Diabetes is characterized by elevated blood glucose levels due to insulin deficiency, resistance or a combination of both. The disease is associated with several complications, and some of these complications are attributed to glycation of proteins which impairs their function and stability. Diabetic foot ulcers (DFUs) are one of the most catastrophic and costly complications of diabetes. These foot ulcers do not naturally progress through the phases of the wound healing process and are therefore classified as chronic wounds. There is limited treatment availability for diabetic foot ulcers, and the current treatment strategies have been met with high rates of recurrence and failure. Therefore, there is need for more extensive research to be conducted to improve therapy and minimize the chance of developing complications. Blood platelets play a central role in initiation of wound healing and on account of this, the study was directed towards comparing platelet proteins from diabetic patients and non-diabetic healthy individuals to investigate the possible differences in protein expression and glycation. The aim was to characterize these proteins to further understand the role platelets play in impaired wound healing in DFUs and to provide a possible basis in developing targeted therapies.
Methods: All blood samples were tested for HbA1c levels which is an indicator of long term blood glucose levels. This was used as a screening tool to confirm participant status. After the screening test, non-stimulated platelets were isolated from whole blood of diabetic patients and non-diabetic healthy individuals, washed and the total protein complement separated using sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The gels were visualized using Stain-free™ imaging and then separately stained with Acqua (colloidal Coomassie blue), silver, Oriole™ or Periodic Acid-Schiff (PAS) stains for comparison. Following this, high performance liquid chromatography (HPLC) coupled to fluorescence detection and western blotting were done to check for possible formation of advanced glycation end products (AGEs).
In-gel and in-solution trypsin digests of selected samples exhibiting protein band differences between the two groups were performed, followed by peptide sequencing using liquid chromatography tandem mass spectrometry (LC-MS/MS).
Results and discussion: Gel electrophoresis results showed similarities in the general pattern of the protein mass fingerprint with subtle band differences identified between the two groups. Results from the PAS stain implied that there was no glycation of platelet proteins in diabetic patients, which led to the proposition that complex advanced AGEs may be forming. This was tested using HPLC with fluorescence detection of the trypsinized samples and the appearance of extra peaks from diabetic patient samples on the chromatograms obtained after HPLC analysis indicated that this was a possibility. Western blotting to confirm the formation of AGEs, showed similarities in the formation of AGEs between the two groups suggesting that there was no difference in AGE formation between diabetic patients and non-diabetic healthy individuals.
A few differences in platelet protein abundance were seen between the two groups when downstream LC-MS/MS analysis of the samples was done, which showed the superiority of the analysis technique over SDS-PAGE.
Conclusion: The study showed that there were no significant differences in glycation of proteins between the two groups which can possibly eliminate glycation as a potential cause of delayed healing of DFUs. However, LC-MS/MS analysis of samples identified proteins which had differences in abundance between the diabetic patients and non-diabetic healthy individuals, some of which are key proteins in the wound healing process. Therefore, based on these results, a proposition can be made that differences in the abundance of these proteins could be contributing to delayed wound healing of DFUs. Due to this, use of autologous platelet rich plasma from diabetic patients to promote healing of DFUs would result in little treatment enhancement as these platelets show proteomic differences that could provide an excess of undesirable proteins at the wound site. Thus, the study can be supplemented with other studies to make a more substantiated conclusion and possibly develop therapies targeted at these proteins. / Dissertation (MSc)--University of Pretoria, 2018. / Pharmacology / MSc / Unrestricted
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The experiences of families regarding caring for family members who are terminally illMnisi, Pretty Pertunia January 2018 (has links)
Caring for terminally ill patients can be regarded as an important public health concern in South Africa. In Sub-Saharan Africa, the Human Immunodeficiency Virus (HIV) or Acquired Immune Deficiency Syndrome (AIDS) and cancer are the most pressing concerns, with 22.5 million infected people in 2009, which means that two thirds (68%) of the global population is living with HIV/AIDS (Pool, 2011:10). It is generally known that South Africa is a leading country in Sub-Saharan Africa in the provision of palliative care. Previous research studies also revealed that many terminally ill patients are voicing the desire to die at home instead of in a hospital or in other health care institutions, which place an unbearable pressure on families. Family caregiving is generally provided by close family members of the terminally ill patient. Providing care to a family member with a terminal illness at home presents with several challenges, such as the fact that taking care of the terminally ill patient is time consuming, which may lead to feelings of social isolation.
The goal of the research study was to explore the experiences of families regarding caring for family members who are terminally ill at home in the community of Ehlanzeni District in the Mpumalanga Province. The guiding research question was: What are the experiences of families regarding caring for family members who are terminally ill living in Ehlanzeni District in the Mpumalanga Province?
A qualitative research approach was followed, with a collective case study as research design. The population for this study was family members who lived with a terminally ill patient. Non-probability, purposive sampling was applied to generate a sample. The sample size of the study was 11 participants between the ages of 18 and 62 years. Semi-structured interviews were used to collect the data, supported by an interview schedule to explore the experiences of family members regarding caring for terminally ill family members. All interviews were voice recorded with the consent of the participants. The data that was gathered by the researcher were analysed and themes and sub-themes were identified.
The empirical findings of the study indicated that the physical demands of family caregiving for a family member with a terminal illness at home are often too much for families to handle on their own without the support of other professional systems. It also revealed that these caregivers, who are mostly females, often present with poor health themselves because of the pressure they experience during the caring process. Some of the family caregivers feel isolated, as they do not have enough time for themselves or for the other family members due to the fact that family caregiving demands almost all of their time. Some of these caregivers face financial constraints, their children‟s school performance decreases, and they are living in poverty-stricken conditions. Some of the participants indicated that family caregiving does have a positive side too, namely that they can take care of a family member, which is a symbol of love and respect.
Conclusions and recommendations were formulated which focus primarily on the role of health professionals, including social workers, in providing a quality service to the terminally ill patients and their families. Themes for further research in this professional field were indicated. / Social Work and Criminology / MSW / Unrestricted
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Mothering across borders : Basotho migrant women in domestic work in PretoriaMoeletsi, Kelebogile January 2017 (has links)
No abstract / Mini Dissertation (MSocSci)--University of Pretoria, 2017. / Sociology / MSocSci / Unrestricted
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Indigenous pathways to appraisal during resilience processesMohamed, Safia January 2017 (has links)
This comparative case study formed part of the Indigenous Pathways to Resilience (IPR) project which aims to
contribute to an indigenous psychology knowledge base on resilience from an African perspective. This study
focused on contributing knowledge on indigenous pathways to appraisal processes as part of resilience
processes to mostly Western-orientated discourses.
IPR situated its investigation in two conveniently selected rural South African communities who
experience chronic circumstances of high risk and high need and had non-Western worldviews. Participants from
the two research sites were stratified according to location, age and gender. Indigenous Psychology (IP) was
selected as the theoretical paradigm for the study, with post-colonial research paradigm as the meta-theoretical
lens. Participatory reflection and action (PRA) served as the methodological paradigm to generate data in two
waves over a period of two years (eight days per site). Data sources included textual data (verbatim transcripts of
audio-recorded PRA activities translated into English) and observation data (researchers’ field notes and
observations). Trustworthiness was enhanced by capturing the process and context visually over time. Data was
analysed using thematic in-case and cross-case analysis lead to inductive themes indigenous pathways to
appraisal during resilience processes.
This study contributes a novel insight into (African) non-Western appraisal processes as part of resilience.
It points to interconnectedness (interpersonal, spiritual and environmental) as a core worldview point of departure
during appraisals. Appraisal from a non-Western (African) perspective is then followed by collaborative appraisal
processes, including consultation and consensus for problem solving. The non-Western (African) appraisal
converges in agency as motivation. This study was delimited to. / Thesis (PhD)--University of Pretoria, 2017. / Educational Psychology / PhD / Unrestricted
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Engineering nature-inspired heuristics for the open shortest path first weight setting problemMohiuddin, Aijaz January 2018 (has links)
Very little guidance exists on the design of steel column base connections for biaxial flexure combined with axial
compression. This study aims to develop a design method for designing these connections for combined loading.
To this end, an extensive experimental programme that consisted of 32 tests to failure, was carried out. The
programme varied plate thickness, holding-down bolt diameter, axial force level and loading angle. Ancillary
tests were carried out to establish material strengths and to assess the importance of bond to the design of the
connection. The programme was augmented with detailed finite element analyses that were calibrated with the
experimental results.
It was found that the contribution of bond to the final anchorage strength of the connection is negligible and should
be ignored. Very little concrete damage was observed during the experimental phase and current design guidance
for concrete bearing strength is very conservative. Increases in plate thickness, holding-down bolt diameter and
axial force were found to increase the connection strength. Increases in loading angle, from strong-axis to weakaxis
bending were found to decrease connection strength. Furthermore, the plate thickness and holding-down bolt
parameters were found to be interdependent. Increases in axial compression were found to increase the initial
connection stiffness.
Finally, a new mechanical model is proposed for designing base connection. The model enables the construction
of thrust-moment interaction diagrams that can be used directly for design. A shortened listing of the source code
used to generate the interaction curve in this work is included in the Appendix. / Thesis (PhD)--University of Pretoria, 2018. / Computer Science / PhD / Unrestricted
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Student perceptions of blended learning interventions in teaching auditingBeukes, Bernice January 2018 (has links)
Education, and especially accounting education, has been criticised for not delivering
graduates for the work place with the necessary skills and attributes. In an effort to
address this criticism, lecturers incorporate more experiential learning into the
curriculum. However, in a quest to include more experiential learning activities in the
course delivery, lecturing time is reduced, and lecturers have to innovate in order to fit
all the subject/course content into the allotted time. Incorporating technology to extend
the classroom into the digital realm is one way to relieve the pressure of covering
subject/course content. It opens up avenues for a blended or hybrid learning model,
where a carefully considered combination of online and face-to-face teaching and
learning is applied.
Auditing as a discipline poses another challenge to educators. The subject is
perceived by students to be very theoretical, while in fact it is an application subject
which requires critical thinking and professional judgment. Students incur difficulties in
comprehending how the theoretical knowledge is applied in practice, which manifests
in them following a superficial approach to mastering the auditing subject matter. In an
effort to breach the gap between theory and practice, various implementations of
experiential learning in auditing, often in a blended learning environment, have been
reported by scholars. However, those studies report the effect of fragmented
interventions and fail to provide a holistic view of the effect of multiple blended learning
interventions. Furthermore, literature on the effect of a blended learning approach
incorporating experiential learning which focuses on learning is limited, and studies
are mainly done in small class settings.
This study aims to expand on the body of knowledge, by reporting on how students
perceived different blended learning elements (flipped classroom, an online simulation
and cooperative learning initiatives), incorporated in the holistic blended learning
model in an auditing module/course, to contribute to their learning and engagement
with the subject matter. Furthermore, the study investigates how the perceived contribution differs between students with different academic performance levels. The
study also determines whether one of the blended learning elements (an online
simulation) was perceived by students to be useful, easy to use and influenced their
emotional perception (affect) of the learning experience. In order to achieve the
objective of the study, a quantitative research approach was followed, whereby a
custom-developed survey was distributed amongst third year auditing students at the
university where the study was performed.
The findings in this study indicate that respondents perceived weekly tutorials to
contribute highly towards their learning of and engagement with auditing, while the
other flipped classroom elements (videos and lectures) had a moderate contribution.
Respondents perceived the online simulation, and peer feedback and mentoring (TUT
Buddy and the BuddyM) elements to contribute least to their learning and engagement
with the auditing subject matter.
Statistically significant differences were identified between high performing and low
performing students, with regard to the weekly tutorials, the online simulation and the
TUT Buddy and BuddyM elements. Low performing students perceived the online
simulation, the TUT Buddy and BuddyM elements to contribute more to their learning
and engagement, than high performing students. These latter three elements (online
simulation and Buddy activities) included more cooperative learning and were
regarded as student-driven activities. The results also indicate that high performing
students coped well with the blended learning model and exhibited characteristics of
becoming self-directed learners, as they did not require as much support. The low
performing students were more positive about cooperative learning activities. They
also perceived the online simulation to be more useful, easy to use and enjoyed the
experience more, compared to their medium and high performing counterparts. The
results clearly show that students do have preference for specific elements in the
holistic blend. The holistic blend allows room to meet the needs of diverse students
with different learning preferences and it allows students to engage with the auditing
subject matter in a way that meets their preferences, whilst developing additional skills.
Therefore a holistic blended learning model appears to be an acceptable way of
teaching auditing, even in large class settings. / Dissertation (MCom)--University of Pretoria, 2018. / Auditing / MCom
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Evaluating rural household demand for improved water quality : a case of rural settlements of Qiloane community in LesothoMokhothu, Elliot Tsepiso January 2018 (has links)
This study analyses the demand for quality water supply services in the rural settlements of the Qiloane community. This is a non-market valuation of preferences for quality water supply services given no explicit market at the study location. The study was implemented in response to increasing problems regarding water supply provision in the Qiloane rural locations of Lesotho. Understanding the demand and willingness to pay for improved quality of water supply service is required to make a case for the provision of the service at Qiloane locations. The results provide evidence that in the Qiloane rural community locations, the households are prepared to pay more than the present price for water. The educational level of the household, spending power (monthly income), and households’ perception regarding the existing water supply quality situation were perceived to be important factors establishing the willingness to pay (WTP) of the rural households. Hence, a beneficial policy decision, applied through a water tariff to enhance water supply services, would need to cautiously take into consideration the capacity to pay through expenditure classes. The results also showed that the demand-driven management technique might reinforce water supply enhancements and feasibility. The study utilised a single-bounded format that elicited responses, expressed through respondents’ WTP, to assess whether a presented improvement cost would influence the WTP of the households for satisfying their demand for water quality supply service enhancements in the Qiloane rural community locations of Lesotho. The Qiloane rural community locations were purposely selected because of the poor water supply services prevailing within the said communities. The WTP of Qiloane rural dwellers for enhanced water supply services was thereby educed through notionally acceptable levels of payment for water equipment installations and monthly water fees. Consistent with recent literature on choice elicitations, the referendum question was followed by a certainty calibration approach whereby respondents were requested to specify their extent of certainty to the referendum question for the purpose of mitigating hypothetical bias problem. The Qiloane rural community locations were identified owing to their depressing water supply services; accordingly, the survey data from 106 households was analysed using purposive and simple random sampling techniques, focus group dialogs, a structured questionnaire and in-person interviews.
Generally, the households of Qiloane rural residents demonstrated a high degree of knowledge concerning the dangers related to the poorly managed water supply service, and the perception of the health risk is high. Further analysis from the study indicated that in regions where water supply service management is presently offered at a fee, the households demonstrated a WTP considerably higher than the existing fees for reformed services. Additionally, the study revealed that in community locations where no water supply service management is presently provided, the households indicated that they are willing to pay a monthly fee of M250 or even more if such services were to be offered. The outcomes of this study can be used by the water supply service management to conduct a cost–benefit analysis, comparing tariff potential with the expense of delivering the service.
According to the outcomes of the survey, the Water and Sewerage Company (WASCO) has a potential to improve the quality of water supply service management practices in locations where they are presently offered at a tariff, and also to offer such services at a fee in regions where they are not presently offered. The analysis from the findings suggests that WASCO could impose a tariff from M250 to M350 for each household on a monthly basis, but still considering the average income classes of the households. However, the substantial monthly fee should be quantified through engagement with the stakeholders concerned. / Dissertation (MSc (Agric))--University of Pretoria, 2018. / Agricultural Economics, Extension and Rural Development / MSc (Agric) / Unrestricted
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The resilience of adolescents at risk of relapse to substance abuseMokwena, Augustus Christof January 2018 (has links)
Substance abuse has become a global scourge wreaking havoc amongst young people across cities and towns, not excluding Eersterust, a small township to the east of Pretoria. The primary purpose of this study is to discover what causes some young people to triumph over their addiction in what seems an almost impossible feat. Answers to the questions of what young people relate as contributors and detractors to resilience are therefore explored.
The empirical part of this study was conducted in the township of Eersterust which has extensive drug abuse amongst community members. The participants, four in total, were purposively sampled from the local high school and rehabilitation centres in the area. The participants were required not to be younger than 18 years with a history of drug abuse and a minimum rehabilitated period of six months.
A qualitative process of life history research was employed to source the narratives of the participants. Bronfenbrenner’s socio-ecological model also served as theoretical framework in this study. Life maps and semi-structured questionnaires were also used to enrich and validate the data. Interviews were recorded and transcribed and the re-storying of the narratives of the participants was done from these transcriptions. The data was subjected to both inductive and deductive processes with a view to firstly generate new theory, and to then test existing theory.
The major themes related to detractors of resilience were: problematic parental styles; rejection by family and peers; low self-esteem due to view of self and perceived rejection; and pemissive normative climate/uninvolved and resource constrained communities. Themes related to resilience were: religion/faith; development of internal locus of control; hope; optimism; role models and mentors; and self-awareness and introspection.
In conclusion, this study has once more highlighted the pivotal role of parents and family as ameliorating factors in adolescent drug abuse. On the other hand, problematic parental styles as contributing factors to adolescent drug abuse have also significantly come through in this study. A final observation of this study was that resilience is indeed a dynamic process. Therefore, the identified themes in favour of resilience in this study cannot be regarded as a blueprint for every single case of addiction recovery. / Dissertation (MEd)--University of Pretoria, 2018. / Early Childhood Education / MEd / Unrestricted
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A mechanistic-empirical method for characterisation of railway track formationMones Ruiz Martin, Alejandro January 2018 (has links)
The demand on South African railway freight lines is growing constantly with respect to train speeds
and axle loading, thus increasing the forces and stresses experienced by the track structure. This may
lead to rapid track deterioration as a result of a loss in track geometry caused by the poor and nonuniform
underlying support. The railway engineering industry has moved towards gaining a better
understanding of track formation behaviour for development of practical and effective deflection
measurement techniques that allow accurate determination of formation structural capacity,
identification of track problem areas and evaluation of track condition. Thus, there is a need to
develop a deflection measurement method that can accurately evaluate the track formation condition
through analysis of the full deflection basin under train passage, in order to quantify the formation
structural capacity based on the relevant in-service conditions.
In this research study, a mechanistic-empirical method (referred to as the inverse method) is proposed
with the main objective of developing an alternative method for evaluation of formation layer
structural capacity through the inverse estimation of formation layers’ elastic moduli. The method
was founded on surface deflection theory from falling weight deflectometer (FWD) analysis. Finite
element analysis and field data from railway substructure deflections under train transient loading obtained through multi-depth deflectometers (MDDs) were used to assess the validity of the inverse
method by comparing measured and modelled railway substructure responses.
The results showed that substructure deflections and stresses are affected by the complex
superposition of different bogie loading configurations on a particular superstructure. The increase
in axle loading was found to be directly proportional to the increase in formation peak deflection.
The effect of travelling speed was however insignificant for speeds less than 80 km/h. Furthermore,
the load distribution in the railway substructure did not follow a 45o influence line as commonly
assumed in surface deflection theory. On the contrary, railway equilibrium influence lines (EILs)
were significantly influenced by the elastic moduli of the formation layers and in-situ subgrade,
therefore governed by the structural capacity of the substructure layers.
The research therefore concluded that the formation layers are expected to gradually deteriorate and
experience increased deflections over time. However, the top of formation may vary as it seems to
be highly influenced by the superstructure load distribution. The inverse method strongly agreed with
the long-term formation peak strains measured with MDDs. Furthermore, the method was
determined suitable for evaluation of formation structural capacity, as good agreement was found
between the measured and estimated formation layers’ elastic moduli. / Dissertation (MEng)--University of Pretoria, 2018. / Civil Engineering / MEng / Unrestricted
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