An investigation into the impact of geographical location on the phytochemical composition, pharmacological and toxicological activities of Tulbaghia violacea collected from the Eastern Cape and Gauteng Province
- Authors: Kader, Tasmeera
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/461819 , vital:76242
- Description: Introduction: The number of communicable and non-communicable diseases continues to rise and has become more prevalent. While drugs exist to manage and/ or treat majority of the communicable and non-communicable diseases, the rise in disease prevalence puts pressure on researchers to find new drug molecules to treat and manage these ailments. Traditional medicine refers to the knowledge, skills and practices which are based on the beliefs and experiences indigenous to cultures and is used to maintain health. Most of the research into traditional medicine focuses on the medicinal plants used. Medicinal plants are any plants in which one or more of its organs contain substances which are used for therapeutic purposes or for the synthesis of drugs. Tulbaghia violacea is a monocotyledonous genus of herbaceous perennial bulbs which is native to Africa and can be readily found throughout South Africa. It is popular for its antimicrobial, antifungal, anticoagulant, antioxidant and anticancer properties. It has been that ecological factors influence the composition and quantity of phytochemicals present in a plant. Aim of the study: The aim of the study was to investigate the impact of geographical location on the phytochemical composition, pharmacological and toxicological activities of T. violacea collected from the Eastern Cape and Gauteng Province. Methods: The leaves of T. violacea were collected from the Eastern Cape and Gauteng Province. The leaves were dried and extracted using serial maceration with solvents hexane, acetone and methanol. The resulting extracts were subjected to qualitative preliminary phytochemical analysis and a quantitative total phenol content test was carried out using gallic acid as the standard. Thin layer chromatography (TLC) was performed to identify classes of compounds present in T. violacea. xix Antioxidant activity of T. violacea was determined qualitatively using a dot-plot and quantitatively using a DPPH radical scavenging activity assay. Ascorbic acid was used as the standard. Anti-diabetic properties of T. violacea were assessed using an α- amylase inhibition assay and an α- glucosidase inhibition assay. Acarbose was used as the standard for these assays. The anti-Alzheimer properties of T. violacea leaf extracts was determined using and acetylcholinesterase (AChE) inhibition assay. Donepezil was used as the standard for this assay. The DPPH radical scavenging activity, the α- amylase inhibition assay, the α- glucosidase inhibition assay and the AChE inhibition assay was combined with linear regression to determine the IC50 values of the T. violacea extracts and the standards. Statistical analysis was conducted to determine any differences between the plant samples and the standards as well as any differences between the EC and GP sample. Results: The results of the qualitative phytochemical analysis revealed the presence of saponins, flavonoids, tannins, alkaloids, steroids, cardiac glycosides and phenolic compounds present in T. violacea collected from EC and GP. However, their presence in the samples were different based on where the plant was cultivated. The results of the total phenolic content test, revealed that the hexane, acetone and methanol extracts of T. violacea contained phenolic compounds with the highest quantity of phenolic compounds being present in the methanol extracts. Significant statistical difference in total phenolic content between the EC and GP samples were seen for the hexane and methanol extracts. The results of the TLC revealed the presence of multiple bands which confirmed the presence of multiple phytochemicals in T. violacea. All of the extracts of T. violacea from EC and GP, showed antioxidant activity using both the dot-plot and the DPPH radical scavenging activity assay. The highest DPPH radical scavenging activity was seen by the hexane extract of the EC sample of T. violacea. The results showed significant statistical difference between the DPPH radical scavenging activity of the EC and GP samples. , Thesis (Msc (Pharmacy)) -- Faculty of Pharmacy, Pharmacy, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Kader, Tasmeera
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/461819 , vital:76242
- Description: Introduction: The number of communicable and non-communicable diseases continues to rise and has become more prevalent. While drugs exist to manage and/ or treat majority of the communicable and non-communicable diseases, the rise in disease prevalence puts pressure on researchers to find new drug molecules to treat and manage these ailments. Traditional medicine refers to the knowledge, skills and practices which are based on the beliefs and experiences indigenous to cultures and is used to maintain health. Most of the research into traditional medicine focuses on the medicinal plants used. Medicinal plants are any plants in which one or more of its organs contain substances which are used for therapeutic purposes or for the synthesis of drugs. Tulbaghia violacea is a monocotyledonous genus of herbaceous perennial bulbs which is native to Africa and can be readily found throughout South Africa. It is popular for its antimicrobial, antifungal, anticoagulant, antioxidant and anticancer properties. It has been that ecological factors influence the composition and quantity of phytochemicals present in a plant. Aim of the study: The aim of the study was to investigate the impact of geographical location on the phytochemical composition, pharmacological and toxicological activities of T. violacea collected from the Eastern Cape and Gauteng Province. Methods: The leaves of T. violacea were collected from the Eastern Cape and Gauteng Province. The leaves were dried and extracted using serial maceration with solvents hexane, acetone and methanol. The resulting extracts were subjected to qualitative preliminary phytochemical analysis and a quantitative total phenol content test was carried out using gallic acid as the standard. Thin layer chromatography (TLC) was performed to identify classes of compounds present in T. violacea. xix Antioxidant activity of T. violacea was determined qualitatively using a dot-plot and quantitatively using a DPPH radical scavenging activity assay. Ascorbic acid was used as the standard. Anti-diabetic properties of T. violacea were assessed using an α- amylase inhibition assay and an α- glucosidase inhibition assay. Acarbose was used as the standard for these assays. The anti-Alzheimer properties of T. violacea leaf extracts was determined using and acetylcholinesterase (AChE) inhibition assay. Donepezil was used as the standard for this assay. The DPPH radical scavenging activity, the α- amylase inhibition assay, the α- glucosidase inhibition assay and the AChE inhibition assay was combined with linear regression to determine the IC50 values of the T. violacea extracts and the standards. Statistical analysis was conducted to determine any differences between the plant samples and the standards as well as any differences between the EC and GP sample. Results: The results of the qualitative phytochemical analysis revealed the presence of saponins, flavonoids, tannins, alkaloids, steroids, cardiac glycosides and phenolic compounds present in T. violacea collected from EC and GP. However, their presence in the samples were different based on where the plant was cultivated. The results of the total phenolic content test, revealed that the hexane, acetone and methanol extracts of T. violacea contained phenolic compounds with the highest quantity of phenolic compounds being present in the methanol extracts. Significant statistical difference in total phenolic content between the EC and GP samples were seen for the hexane and methanol extracts. The results of the TLC revealed the presence of multiple bands which confirmed the presence of multiple phytochemicals in T. violacea. All of the extracts of T. violacea from EC and GP, showed antioxidant activity using both the dot-plot and the DPPH radical scavenging activity assay. The highest DPPH radical scavenging activity was seen by the hexane extract of the EC sample of T. violacea. The results showed significant statistical difference between the DPPH radical scavenging activity of the EC and GP samples. , Thesis (Msc (Pharmacy)) -- Faculty of Pharmacy, Pharmacy, 2024
- Full Text:
- Date Issued: 2024-10-11
Towards a valid Afrikaans-translation of the CASr-SF: a linguistic and cultural transfer
- Authors: Steyn, Constanze
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/465854 , vital:76659
- Description: Globally, and especially in South Africa, we face the reality of linguistic and cultural variation within one nation. Our nation is intricately woven from rich cultural and linguistic threads to create a complex tapestry. It is a beautiful privilege that is, however, not without its obstacles. We often do not have access to psychometric tools that “speak” the language of the respondent that we intend to assess. It is, and should, however, be, our goal to adapt and translate assessments to allow individuals to convey their experience in their language of comfort. This is crucial for psychological assessments' fairness, reliability, validity, and utility. Intimate partner violence (IPV) severely impacts mental health worldwide. An alarming correlation has been found between exposure to IPV and the development of mental health difficulties. In South Africa, IPV is considered a significant public health issue. Even though South Africa has a population of approximately 60,9 million, of whom an estimated 10.6% are Afrikaans-speaking, there is currently no measure exploring the experiences of IPV available in Afrikaans. Having psychological assessments available in Afrikaans is essential in evaluating the psychological experiences of people seeking mental health services in Afrikaans. The Composite Abuse Scale (Revised) – Short Form (CASr-SF) is a self-report questionnaire that measures experiences of IPV across three domains: physical, psychological, and sexual abuse. This study aimed to develop a meaningful and relevant Afrikaans translation of the CASr-SF to improve the linguistic accessibility of the measure and afford more ease to Afrikaans-speaking individuals in sharing experiences of abuse. This study followed a four-step translation design, including forward- and backtranslation, a committee approach, and qualitative piloting through cognitive interviews. Participants in this study included four independent translators who were approached by the researcher directly, according to their respective areas of expertise – linguistics and psychology. In addition, three participants were sourced from the target population through snowball sampling to partake in cognitive interviews as a confirmatory step and to potentially substantiate, expand on, and review results gathered during the first three steps of the translation design. The researcher ii compared, collated, and analysed the data to identify problematic items. The translation team then discussed these items to refine the translation, and items were corrected to develop the final translation of the Composite Abuse Scale (Revised) – Short Form in Afrikaans. The translation is now ready for quantitative piloting, which is currently underway to establish its psychometric properties. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Steyn, Constanze
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/465854 , vital:76659
- Description: Globally, and especially in South Africa, we face the reality of linguistic and cultural variation within one nation. Our nation is intricately woven from rich cultural and linguistic threads to create a complex tapestry. It is a beautiful privilege that is, however, not without its obstacles. We often do not have access to psychometric tools that “speak” the language of the respondent that we intend to assess. It is, and should, however, be, our goal to adapt and translate assessments to allow individuals to convey their experience in their language of comfort. This is crucial for psychological assessments' fairness, reliability, validity, and utility. Intimate partner violence (IPV) severely impacts mental health worldwide. An alarming correlation has been found between exposure to IPV and the development of mental health difficulties. In South Africa, IPV is considered a significant public health issue. Even though South Africa has a population of approximately 60,9 million, of whom an estimated 10.6% are Afrikaans-speaking, there is currently no measure exploring the experiences of IPV available in Afrikaans. Having psychological assessments available in Afrikaans is essential in evaluating the psychological experiences of people seeking mental health services in Afrikaans. The Composite Abuse Scale (Revised) – Short Form (CASr-SF) is a self-report questionnaire that measures experiences of IPV across three domains: physical, psychological, and sexual abuse. This study aimed to develop a meaningful and relevant Afrikaans translation of the CASr-SF to improve the linguistic accessibility of the measure and afford more ease to Afrikaans-speaking individuals in sharing experiences of abuse. This study followed a four-step translation design, including forward- and backtranslation, a committee approach, and qualitative piloting through cognitive interviews. Participants in this study included four independent translators who were approached by the researcher directly, according to their respective areas of expertise – linguistics and psychology. In addition, three participants were sourced from the target population through snowball sampling to partake in cognitive interviews as a confirmatory step and to potentially substantiate, expand on, and review results gathered during the first three steps of the translation design. The researcher ii compared, collated, and analysed the data to identify problematic items. The translation team then discussed these items to refine the translation, and items were corrected to develop the final translation of the Composite Abuse Scale (Revised) – Short Form in Afrikaans. The translation is now ready for quantitative piloting, which is currently underway to establish its psychometric properties. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
- Full Text:
- Date Issued: 2024-10-11
A Comparison of Mitochondrial Heat Shock Protein 70 and Hsp70 Escort Protein 1 Orthologues from Trypanosoma brucei and Homo sapiens
- Authors: Hand, Francis Bryan
- Date: 2023-03-29
- Subjects: Trypanosoma brucei , Heat shock proteins , Molecular chaperones , Transport protein , AlphaFold , Mitochondrial heat shock protein
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/422281 , vital:71927
- Description: The causative agent of African trypanosomiasis, Trypanosoma brucei (T. brucei), has an expanded retinue of specialized heat shock proteins, which have been identified as crucial to the progression of the disease. These play a central role in disease progression and transmission through their involvement in cell-cycle pathways which bring about cell-cycle arrest and differentiation. Hsp70 proteins are essential for the maintenance of proteostasis in the cell. Mitochondrial Hsp70 (mtHsp70) is a highly conserved molecular chaperone required for both the translocation of nuclear encoded proteins across the two mitochondrial membranes and the subsequent folding of proteins in the matrix. The T. brucei genome encodes three copies of mtHsp70 which are 100% identical. MtHsp70 self-aggregates, a property unique to this isoform, and an Hsp70 escort protein (Hep1) is required to maintain the molecular chaperone in a soluble, functional state. This study aimed to compare the solubilizing interaction of Hep1 from T. brucei and Homo sapiens (H. sapien). The recently introduced Alphafold program was used to analyze the structures of mtHsp70 and Hep1 proteins and allowed observations of structures unavailable to other modelling techniques. The GVFEV motif found in the ATPase domain of mtHsp70s interacted with the linker region, resulting in aggregation, the Alphafold models produced indicated that the replacement of the lysine (K) residue within the KTFEV motif of DnaK (prokaryotic Hsp70) with Glycine (G), may abrogate bond formation between the motif and a region between lobe I and II of the ATPase domain. This may facilitate the aggregation reaction of mtHsp70 orthologues and provides a residue of interest for future studies. Both TbHep1 and HsHep1 reduced the thermal aggregation of TbmtHsp70 and mortalin (H. sapien mtHsp70) respectively, however, TbHep1 was ~ 15 % less effective than HsHep1 at higher concentrations (4 uM). TbHep1 itself appeared to be aggregation-prone when under conditions of thermal stress, Alphafold models suggest this may be due to an N-terminal α- helical structure not present in HsHep1. These results indicate that TbHep1 is functionally similar to HsHep1, however, the orthologue may operate in a unique manner which requires further investigation. , Thesis (MSc) -- Faculty of Science, Biotechnology Innovation Centre, 2023
- Full Text:
- Date Issued: 2023-03-29
- Authors: Hand, Francis Bryan
- Date: 2023-03-29
- Subjects: Trypanosoma brucei , Heat shock proteins , Molecular chaperones , Transport protein , AlphaFold , Mitochondrial heat shock protein
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/422281 , vital:71927
- Description: The causative agent of African trypanosomiasis, Trypanosoma brucei (T. brucei), has an expanded retinue of specialized heat shock proteins, which have been identified as crucial to the progression of the disease. These play a central role in disease progression and transmission through their involvement in cell-cycle pathways which bring about cell-cycle arrest and differentiation. Hsp70 proteins are essential for the maintenance of proteostasis in the cell. Mitochondrial Hsp70 (mtHsp70) is a highly conserved molecular chaperone required for both the translocation of nuclear encoded proteins across the two mitochondrial membranes and the subsequent folding of proteins in the matrix. The T. brucei genome encodes three copies of mtHsp70 which are 100% identical. MtHsp70 self-aggregates, a property unique to this isoform, and an Hsp70 escort protein (Hep1) is required to maintain the molecular chaperone in a soluble, functional state. This study aimed to compare the solubilizing interaction of Hep1 from T. brucei and Homo sapiens (H. sapien). The recently introduced Alphafold program was used to analyze the structures of mtHsp70 and Hep1 proteins and allowed observations of structures unavailable to other modelling techniques. The GVFEV motif found in the ATPase domain of mtHsp70s interacted with the linker region, resulting in aggregation, the Alphafold models produced indicated that the replacement of the lysine (K) residue within the KTFEV motif of DnaK (prokaryotic Hsp70) with Glycine (G), may abrogate bond formation between the motif and a region between lobe I and II of the ATPase domain. This may facilitate the aggregation reaction of mtHsp70 orthologues and provides a residue of interest for future studies. Both TbHep1 and HsHep1 reduced the thermal aggregation of TbmtHsp70 and mortalin (H. sapien mtHsp70) respectively, however, TbHep1 was ~ 15 % less effective than HsHep1 at higher concentrations (4 uM). TbHep1 itself appeared to be aggregation-prone when under conditions of thermal stress, Alphafold models suggest this may be due to an N-terminal α- helical structure not present in HsHep1. These results indicate that TbHep1 is functionally similar to HsHep1, however, the orthologue may operate in a unique manner which requires further investigation. , Thesis (MSc) -- Faculty of Science, Biotechnology Innovation Centre, 2023
- Full Text:
- Date Issued: 2023-03-29
Genetic analysis and field application of a UV-tolerant strain of CrleGV for improved control of Thaumatotibia leucotreta
- Authors: Bennett, Tahnee Tashia
- Date: 2022-10-14
- Subjects: Cryptophlebia leucotreta Biological control , Pests Integrated control , Biological pest control agents , Ultraviolet radiation , Oligonucleotides
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362741 , vital:65358
- Description: Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), also known as false codling moth (FCM), is indigenous to sub-Saharan Africa. Thaumatotibia leucotreta has been controlled through an integrated pest management (IPM) programme, which includes chemical control, sterile insect technique (SIT), cultural and biological control. As part of the biological control, a key component is the use of Cryptophlebia leucotreta granulovirus (CrleGV-SA). Currently, CryptogranTM, a commercial formulation of CrleGV, is the preferred product to use in South Africa for the control of T. leucotreta. The registration of the biopesticide Cryptogran (River bioscience, South Africa) was established after conducting extensive field trials with CrleGV-SA. One of the major factors affecting the baculovirus efficacy in the field is UV irradiation. A UV-tolerant Cryptophlebia leucotreta granulovirus (CrleGV-SA-C5) isolate was isolated after consecutive cycles of UV exposure. This UV-tolerant isolate is genetically distinct from the CrleGV-SA isolate. The CrleGV-SA-C5 isolate has the potential as a biological control agent. The control of T. leucotreta in South Africa could be improved by the development of novel isolates into new biopesticide formulations. To date, there has not been any field trials conducted on the CrleGV-SA-C5 isolate. Therefore, it is important to determine the biological and genetic stability of this isolate and to conduct field trials with CrleGV-SA- C5 to test the efficacy of the isolate before possible production into a biopesticide. A de novo assembly was conducted to reassemble the genome of CrleGV-SA-C5 which was followed by a sequence comparison with the CrleGV-SA genome. The identification of SNPs, led to the design of oligonucleotides flanking the regions where the SNPs were detected. Polymerase chain reaction amplification of the target regions was conducted using the oligonucleotides. After sequence comparison, seven SNPs were detected and PCR amplification was successful using the three oligonucleotides, Pif-2, HypoP and Lef-8/HP. To differentiate between CrleGV-SA-C5 and CrleGV-SA genomes and confirm the presence of the SNPs, two methods of screening were conducted. The first was the construction of six plasmids, the plasmids contained the targeted pif-2, HypoP, and the Lef-8/HP insert regions from both the CrleGV-SA-C5 and CrleGV-SA genome region where the SNPs were identified, followed by sequencing. The Five recombinant plasmids, pC5_Pif-2, pSA_Pif-2, pC5_HypoP, pSA_HypoP, and pC5_Lef-8/HP were successfully sequenced. No amplicon was obtained for one of the plasmids used as template (pSA_Lef-8/HP) and therefore the PCR product used for cloning was sequenced instead. Sequence alignment confirmed the presence of four of the five targeted SNPs in the genome of the CrleGV-SA-C5 isolate. However, of these only one SNP (UV_7) rendered a suitable marker for the differentiation between the CrleGV-SA-C5 and CrleGV-SA isolates as the SNPs, UV_2, UV_3 and UV_5, were also present in the CrleGV- SA sequences. The second screening method was a quantitative polymerase chain reaction (qPCR) melt curve analysis to differentiate between the CrleGV-SA-C5 and CrleGV-SA isolates. qPCR melt curve analysis was done using the CrleGV-SA-C5 and CrleGV-SA HypoP PCR products. This technique was unable to differentiate between the CrleGV-SA-C5 and CrleGV-SA isolates. However, this may be as a result of sequence data confirming that SNP UV_5 originally identified in the CrleGV-SA-C5 HypoP region was identical to the SNP at the same position in the CrleGV-SA HypoP region. Following the differentiation of the CrleGV-SA-C5 and CrleGV-SA isolates through two screening methods, the genetic integrity of the CrleGV-SA-C5 isolate after two virus bulk-ups was determined by PCR amplification of the target regions in the bulk-up virus followed by sequencing. Prior to virus bulk-up, surface dose bioassays were conducted on 4th instar larvae and LC50 and LC90 values of 4.01 x 106 OBs/ml and 8.75 x 109 OBs/ml respectively were obtained. The CrleGV-SA-C5 isolate was then bulked up in fourth instar T. leucotreta larvae using the LC90 value that was determined. Sequencing of the target regions from the CrleGV- SA-C5_BU2 (bulk-up 2) was conducted. Sequencing results confirmed the presence of the target SNPs in the CrleGV-SA-C5_BU2 genome. The UV-tolerance of the CrleGV-SA-C5 isolate in comparison to the CrleGV-SA isolate was evaluated by detached fruit bioassays under natural UV irradiation. Two detached fruit bioassays were set-up, a UV exposure and a non-UV exposure bioassay set-up. Three treatments were used for each bioassay set-up which were the viruses CrleGV-SA-C5 and CrleGV-SA and a ddH2O control. Statistical analysis indicated that there was no significant difference between the virus treatments in both the UV exposed detached fruit bioassay and the non-UV exposed detached fruit bioassay. This study is the second study to report on the de novo assembly of the CrleGV-SA-C5 and sequence comparison with the CrleGV-SA genome, and the first to report on the UV-tolerance of the CrleGV-SA-C5 isolate by detached fruit bioassays. Future work could involve further evaluation of intraspecific genetic variability in the CrleGV-SA-C5 isolate and to identify any additional SNPs present within the genome that can be used as suitable markers for differentiation between the CrleGV-SA-C5 and CrleGV-SA isolates. It was recognised that it is required to conduct further detached fruit bioassays and field trials, but with improved protocols, for the efficacy and UV-tolerance of the CrleGV-SA-C5 isolate to be conclusively determined. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Bennett, Tahnee Tashia
- Date: 2022-10-14
- Subjects: Cryptophlebia leucotreta Biological control , Pests Integrated control , Biological pest control agents , Ultraviolet radiation , Oligonucleotides
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362741 , vital:65358
- Description: Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), also known as false codling moth (FCM), is indigenous to sub-Saharan Africa. Thaumatotibia leucotreta has been controlled through an integrated pest management (IPM) programme, which includes chemical control, sterile insect technique (SIT), cultural and biological control. As part of the biological control, a key component is the use of Cryptophlebia leucotreta granulovirus (CrleGV-SA). Currently, CryptogranTM, a commercial formulation of CrleGV, is the preferred product to use in South Africa for the control of T. leucotreta. The registration of the biopesticide Cryptogran (River bioscience, South Africa) was established after conducting extensive field trials with CrleGV-SA. One of the major factors affecting the baculovirus efficacy in the field is UV irradiation. A UV-tolerant Cryptophlebia leucotreta granulovirus (CrleGV-SA-C5) isolate was isolated after consecutive cycles of UV exposure. This UV-tolerant isolate is genetically distinct from the CrleGV-SA isolate. The CrleGV-SA-C5 isolate has the potential as a biological control agent. The control of T. leucotreta in South Africa could be improved by the development of novel isolates into new biopesticide formulations. To date, there has not been any field trials conducted on the CrleGV-SA-C5 isolate. Therefore, it is important to determine the biological and genetic stability of this isolate and to conduct field trials with CrleGV-SA- C5 to test the efficacy of the isolate before possible production into a biopesticide. A de novo assembly was conducted to reassemble the genome of CrleGV-SA-C5 which was followed by a sequence comparison with the CrleGV-SA genome. The identification of SNPs, led to the design of oligonucleotides flanking the regions where the SNPs were detected. Polymerase chain reaction amplification of the target regions was conducted using the oligonucleotides. After sequence comparison, seven SNPs were detected and PCR amplification was successful using the three oligonucleotides, Pif-2, HypoP and Lef-8/HP. To differentiate between CrleGV-SA-C5 and CrleGV-SA genomes and confirm the presence of the SNPs, two methods of screening were conducted. The first was the construction of six plasmids, the plasmids contained the targeted pif-2, HypoP, and the Lef-8/HP insert regions from both the CrleGV-SA-C5 and CrleGV-SA genome region where the SNPs were identified, followed by sequencing. The Five recombinant plasmids, pC5_Pif-2, pSA_Pif-2, pC5_HypoP, pSA_HypoP, and pC5_Lef-8/HP were successfully sequenced. No amplicon was obtained for one of the plasmids used as template (pSA_Lef-8/HP) and therefore the PCR product used for cloning was sequenced instead. Sequence alignment confirmed the presence of four of the five targeted SNPs in the genome of the CrleGV-SA-C5 isolate. However, of these only one SNP (UV_7) rendered a suitable marker for the differentiation between the CrleGV-SA-C5 and CrleGV-SA isolates as the SNPs, UV_2, UV_3 and UV_5, were also present in the CrleGV- SA sequences. The second screening method was a quantitative polymerase chain reaction (qPCR) melt curve analysis to differentiate between the CrleGV-SA-C5 and CrleGV-SA isolates. qPCR melt curve analysis was done using the CrleGV-SA-C5 and CrleGV-SA HypoP PCR products. This technique was unable to differentiate between the CrleGV-SA-C5 and CrleGV-SA isolates. However, this may be as a result of sequence data confirming that SNP UV_5 originally identified in the CrleGV-SA-C5 HypoP region was identical to the SNP at the same position in the CrleGV-SA HypoP region. Following the differentiation of the CrleGV-SA-C5 and CrleGV-SA isolates through two screening methods, the genetic integrity of the CrleGV-SA-C5 isolate after two virus bulk-ups was determined by PCR amplification of the target regions in the bulk-up virus followed by sequencing. Prior to virus bulk-up, surface dose bioassays were conducted on 4th instar larvae and LC50 and LC90 values of 4.01 x 106 OBs/ml and 8.75 x 109 OBs/ml respectively were obtained. The CrleGV-SA-C5 isolate was then bulked up in fourth instar T. leucotreta larvae using the LC90 value that was determined. Sequencing of the target regions from the CrleGV- SA-C5_BU2 (bulk-up 2) was conducted. Sequencing results confirmed the presence of the target SNPs in the CrleGV-SA-C5_BU2 genome. The UV-tolerance of the CrleGV-SA-C5 isolate in comparison to the CrleGV-SA isolate was evaluated by detached fruit bioassays under natural UV irradiation. Two detached fruit bioassays were set-up, a UV exposure and a non-UV exposure bioassay set-up. Three treatments were used for each bioassay set-up which were the viruses CrleGV-SA-C5 and CrleGV-SA and a ddH2O control. Statistical analysis indicated that there was no significant difference between the virus treatments in both the UV exposed detached fruit bioassay and the non-UV exposed detached fruit bioassay. This study is the second study to report on the de novo assembly of the CrleGV-SA-C5 and sequence comparison with the CrleGV-SA genome, and the first to report on the UV-tolerance of the CrleGV-SA-C5 isolate by detached fruit bioassays. Future work could involve further evaluation of intraspecific genetic variability in the CrleGV-SA-C5 isolate and to identify any additional SNPs present within the genome that can be used as suitable markers for differentiation between the CrleGV-SA-C5 and CrleGV-SA isolates. It was recognised that it is required to conduct further detached fruit bioassays and field trials, but with improved protocols, for the efficacy and UV-tolerance of the CrleGV-SA-C5 isolate to be conclusively determined. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2022
- Full Text:
- Date Issued: 2022-10-14
Factors influencing the adoption of mobile health monitoring and care systems by the elderly living at home in South Africa: a case of Buffalo City Metropolitan Municipality.
- Authors: Fotoyi, Yolande Odwa
- Date: 2021-09
- Subjects: Medical informatics , Wireless communication systems in medical care
- Language: English
- Type: Master's/ theses , text
- Identifier: http://hdl.handle.net/10353/20406 , vital:45662
- Description: The gradual increase of elderly people around the globe necessitates intensive dialogue amongst government, the healthcare sector and elderly communities as per MPAA 2002 resolutions. Literature identifies technology as the enabler to drive the facilitation of improved living conditions beginning with an affordable, accessible and integrated health information system (HIS). The attainment of a better quality of care to meet the elderly’s needs requires the re-engineering of current modalities. The diverse nature of South Africa is more suited to a people-based rather than a process-centric approach currently in existence. Access barriers, affordability, the digital divide, lack of government buy-in, and fragmented HIS are considered major impediments to adoption of mobile monitoring and care systems (MMCs) for the elderly’s healthcare. Given the complications brought about by the Covid-19 pandemic, the adoption of MMCs cannot be more pronounced. However, despite available literature regarding elderly issues in both developed and developing countries, the elderly plight has still not been considered a national priority. The main purpose of this research was to investigate why elderly people do not adopt MMCs to improve their quality of life, with MMC technologies as a general area of research. The main objective of the study was to develop critical success factors to improve the adoption of MMCs by the elderly living at home. This would potentially alleviate the burden on healthcare resources and also improve the elderly’s quality of life. Primary data collection took place from 21 February to 28 February 2020 in Buffalo City Metropolitan Municipality. Semi-structured interviews were conducted with 15 participants comprising one male and 14 females who represented the elderly Black, Coloured, Indian and White people. This qualitative research tool and purposive sampling method were chosen in order to fully capture the participants’ experiences in the home environment, which excluded those living in frail care or step-down facilities or state institutions. Despite the sample size being small and not being generalizable, it delivered rich information which provided a deeper understanding and fresh insights into the landscape of the elderly and their healthcare needs. The interviews were recorded, transcribed and analysed thematically. The study found that elderly communities are not entirely averse to adoption of MMCs but challenges like affordability and chronic shortage of technical skills prove to be impediments to adoption of MMCs for the elderly’s healthcare. The lack of standardisation and data governance pertaining to data sharing in HISs also serve to exacerbate the matter. The study, therefore, recommends collaborative engagements amongst government, business and the elderly to facilitate the availability of affordable and accessible ICT infrastructure for the elderly communities. Improved adoption of MMCs carry the potential benefit which emanates from the assumption of a pro-active role by the elderly and optimising available MMCs thus reducing strain and freeing-up healthcare workers to concentrate on core duties. The onus thus falls on the healthcare sector to revise the available strategies which seek to enhance the quality of life of the elderly people living in the home environment. , Thesis (MCom) (Information Systems) -- University of Fort Hare, 2021.
- Full Text:
- Date Issued: 2021-09
- Authors: Fotoyi, Yolande Odwa
- Date: 2021-09
- Subjects: Medical informatics , Wireless communication systems in medical care
- Language: English
- Type: Master's/ theses , text
- Identifier: http://hdl.handle.net/10353/20406 , vital:45662
- Description: The gradual increase of elderly people around the globe necessitates intensive dialogue amongst government, the healthcare sector and elderly communities as per MPAA 2002 resolutions. Literature identifies technology as the enabler to drive the facilitation of improved living conditions beginning with an affordable, accessible and integrated health information system (HIS). The attainment of a better quality of care to meet the elderly’s needs requires the re-engineering of current modalities. The diverse nature of South Africa is more suited to a people-based rather than a process-centric approach currently in existence. Access barriers, affordability, the digital divide, lack of government buy-in, and fragmented HIS are considered major impediments to adoption of mobile monitoring and care systems (MMCs) for the elderly’s healthcare. Given the complications brought about by the Covid-19 pandemic, the adoption of MMCs cannot be more pronounced. However, despite available literature regarding elderly issues in both developed and developing countries, the elderly plight has still not been considered a national priority. The main purpose of this research was to investigate why elderly people do not adopt MMCs to improve their quality of life, with MMC technologies as a general area of research. The main objective of the study was to develop critical success factors to improve the adoption of MMCs by the elderly living at home. This would potentially alleviate the burden on healthcare resources and also improve the elderly’s quality of life. Primary data collection took place from 21 February to 28 February 2020 in Buffalo City Metropolitan Municipality. Semi-structured interviews were conducted with 15 participants comprising one male and 14 females who represented the elderly Black, Coloured, Indian and White people. This qualitative research tool and purposive sampling method were chosen in order to fully capture the participants’ experiences in the home environment, which excluded those living in frail care or step-down facilities or state institutions. Despite the sample size being small and not being generalizable, it delivered rich information which provided a deeper understanding and fresh insights into the landscape of the elderly and their healthcare needs. The interviews were recorded, transcribed and analysed thematically. The study found that elderly communities are not entirely averse to adoption of MMCs but challenges like affordability and chronic shortage of technical skills prove to be impediments to adoption of MMCs for the elderly’s healthcare. The lack of standardisation and data governance pertaining to data sharing in HISs also serve to exacerbate the matter. The study, therefore, recommends collaborative engagements amongst government, business and the elderly to facilitate the availability of affordable and accessible ICT infrastructure for the elderly communities. Improved adoption of MMCs carry the potential benefit which emanates from the assumption of a pro-active role by the elderly and optimising available MMCs thus reducing strain and freeing-up healthcare workers to concentrate on core duties. The onus thus falls on the healthcare sector to revise the available strategies which seek to enhance the quality of life of the elderly people living in the home environment. , Thesis (MCom) (Information Systems) -- University of Fort Hare, 2021.
- Full Text:
- Date Issued: 2021-09
The relationship between financial development and energy consumption in South Africa
- Authors: Lefatsa, Palesa Milliscent
- Date: 2021-00
- Subjects: Commerce in Economics
- Language: English
- Type: Masters theses , text
- Identifier: http://hdl.handle.net/11260/10262 , vital:74952
- Description: The study empirically examined the relationship between financial development and energy consumption in South Africa for the period 1980 to 2018. To achieve this objective, the study employed an autoregressive distributed lag bounds technique and Granger causality tests. Financial development, industrialisation, and urbanisation displayed a positive and significant relationship with energy consumption, both in the short run and long run. Economic growth was positive but not significant in the shortrun and long-run. Granger causality test results displayed a unidirectional causality running from financial development and industrialisation to energy consumption. This is in favour of an alternative hypothesis, meaning there is a relationship between financial development and energy consumption in South Africa. This study recommends policies that will allow financial development to stimulate clean energy consumption while considering increases in electricity consumption. The South African government must introduce new financial policies to enhance the process of capitalisation and produce sound energy infrastructure and introduce investments in renewable energy sources to safeguard against carbon emissions. , Thesis (Masters) -- Faculty of Economics and Financial Sciences, 2021
- Full Text:
- Date Issued: 2021-00
- Authors: Lefatsa, Palesa Milliscent
- Date: 2021-00
- Subjects: Commerce in Economics
- Language: English
- Type: Masters theses , text
- Identifier: http://hdl.handle.net/11260/10262 , vital:74952
- Description: The study empirically examined the relationship between financial development and energy consumption in South Africa for the period 1980 to 2018. To achieve this objective, the study employed an autoregressive distributed lag bounds technique and Granger causality tests. Financial development, industrialisation, and urbanisation displayed a positive and significant relationship with energy consumption, both in the short run and long run. Economic growth was positive but not significant in the shortrun and long-run. Granger causality test results displayed a unidirectional causality running from financial development and industrialisation to energy consumption. This is in favour of an alternative hypothesis, meaning there is a relationship between financial development and energy consumption in South Africa. This study recommends policies that will allow financial development to stimulate clean energy consumption while considering increases in electricity consumption. The South African government must introduce new financial policies to enhance the process of capitalisation and produce sound energy infrastructure and introduce investments in renewable energy sources to safeguard against carbon emissions. , Thesis (Masters) -- Faculty of Economics and Financial Sciences, 2021
- Full Text:
- Date Issued: 2021-00
The relationship between financial development and energy consumption in South Africa
- Authors: Lefatsa, Palesa Milliscent
- Date: 2021-00
- Subjects: Commerce in Economics
- Language: English
- Type: Masters theses , text
- Identifier: http://hdl.handle.net/11260/10192 , vital:74948
- Description: The study empirically examined the relationship between financial development and energy consumption in South Africa for the period 1980 to 2018. To achieve this objective, the study employed an autoregressive distributed lag bounds technique and Granger causality tests. Financial development, industrialisation, and urbanisation displayed a positive and significant relationship with energy consumption, both in the short run and long run. Economic growth was positive but not significant in the shortrun and long-run. Granger causality test results displayed a unidirectional causality running from financial development and industrialisation to energy consumption. This is in favour of an alternative hypothesis, meaning there is a relationship between financial development and energy consumption in South Africa. This study recommends policies that will allow financial development to stimulate clean energy consumption while considering increases in electricity consumption. The South African government must introduce new financial policies to enhance the process of capitalisation and produce sound energy infrastructure and introduce investments in renewable energy sources to safeguard against carbon emissions. , Thesis (Masters) -- Faculty of Economics and Financial Sciences, 2021
- Full Text:
- Date Issued: 2021-00
- Authors: Lefatsa, Palesa Milliscent
- Date: 2021-00
- Subjects: Commerce in Economics
- Language: English
- Type: Masters theses , text
- Identifier: http://hdl.handle.net/11260/10192 , vital:74948
- Description: The study empirically examined the relationship between financial development and energy consumption in South Africa for the period 1980 to 2018. To achieve this objective, the study employed an autoregressive distributed lag bounds technique and Granger causality tests. Financial development, industrialisation, and urbanisation displayed a positive and significant relationship with energy consumption, both in the short run and long run. Economic growth was positive but not significant in the shortrun and long-run. Granger causality test results displayed a unidirectional causality running from financial development and industrialisation to energy consumption. This is in favour of an alternative hypothesis, meaning there is a relationship between financial development and energy consumption in South Africa. This study recommends policies that will allow financial development to stimulate clean energy consumption while considering increases in electricity consumption. The South African government must introduce new financial policies to enhance the process of capitalisation and produce sound energy infrastructure and introduce investments in renewable energy sources to safeguard against carbon emissions. , Thesis (Masters) -- Faculty of Economics and Financial Sciences, 2021
- Full Text:
- Date Issued: 2021-00
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