Anticholinesterase and Antioxidant Activities of Spilanthes filicaulis Whole Plant Extracts for the Management of Alzheimer’s Disease
- Elufioye, Taiwo O., Unachukwu, Cynthia C., Oyedeji, Adebola O.
- Authors: Elufioye, Taiwo O. , Unachukwu, Cynthia C. , Oyedeji, Adebola O.
- Date: 2019
- Subjects: Alzheimer’s disease , Cholinesterase inhibitors , Antioxidants , Spilanthes , Flavonoids , Phenolic
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6534 , vital:46450 , xlink:href="https://10.2174/1573408015666190730113405"
- Description: Background: Spilanthes filicaulis is a tropical herb implicated as a memory enhancer in ethnomedicine. Objective: The study investigated acetyl/butyryl cholinesterase inhibitory and antioxidant activities of different extracts of S. filicaulis whole plant and correlated them to its phytochemical constituents. Methods: The powdered whole plant was successively extracted with n-hexane, ethyl acetate and methanol. Acetyl cholinesterase (AChE) and Butyryl cholinesterase (BuChE) inhibitory activity were evaluated by Ellman colorimetry assay. Antioxidant activity was tested using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, ferric reducing power and nitric oxide scavenging assays. Total phenolic, flavonoid and tannin were estimated using standard methods. Correlation was determined using Quest Graph™ Regression Calculator. Results: Various extracts exhibited concentration-dependent AChE and BuChE inhibitory activity with ethyl acetate extract being the highest with IC50 of 0.77 μg/mL and 0.92 μg/mL for AChE and BuChE respectively. The ethyl acetate extract also showed the highest reducing power when compared with the other extracts. The methanol extract had slightly higher phenolic and flavonoid content and showed the highest DPPH radical scavenging effect. DPPH scavenging, AChE and BuChE inhibition had high correlation with the total flavonoid content with R2 values of 1.00, 0.800 and 0.992 respectively while nitric oxide scavenging had high correlation with phenolics and tannins with R2 = 0.942 and 0.806 respectively. Conclusion: These results show that the extracts of the whole plant of S. filicaulis possess significant AChE/BuChE inhibitory and antioxidant properties, mostly due to its flavonoid content, suggesting the possible use of the plant in neurodegenerative diseases such as AD.
- Full Text:
- Date Issued: 2019
- Authors: Elufioye, Taiwo O. , Unachukwu, Cynthia C. , Oyedeji, Adebola O.
- Date: 2019
- Subjects: Alzheimer’s disease , Cholinesterase inhibitors , Antioxidants , Spilanthes , Flavonoids , Phenolic
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6534 , vital:46450 , xlink:href="https://10.2174/1573408015666190730113405"
- Description: Background: Spilanthes filicaulis is a tropical herb implicated as a memory enhancer in ethnomedicine. Objective: The study investigated acetyl/butyryl cholinesterase inhibitory and antioxidant activities of different extracts of S. filicaulis whole plant and correlated them to its phytochemical constituents. Methods: The powdered whole plant was successively extracted with n-hexane, ethyl acetate and methanol. Acetyl cholinesterase (AChE) and Butyryl cholinesterase (BuChE) inhibitory activity were evaluated by Ellman colorimetry assay. Antioxidant activity was tested using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, ferric reducing power and nitric oxide scavenging assays. Total phenolic, flavonoid and tannin were estimated using standard methods. Correlation was determined using Quest Graph™ Regression Calculator. Results: Various extracts exhibited concentration-dependent AChE and BuChE inhibitory activity with ethyl acetate extract being the highest with IC50 of 0.77 μg/mL and 0.92 μg/mL for AChE and BuChE respectively. The ethyl acetate extract also showed the highest reducing power when compared with the other extracts. The methanol extract had slightly higher phenolic and flavonoid content and showed the highest DPPH radical scavenging effect. DPPH scavenging, AChE and BuChE inhibition had high correlation with the total flavonoid content with R2 values of 1.00, 0.800 and 0.992 respectively while nitric oxide scavenging had high correlation with phenolics and tannins with R2 = 0.942 and 0.806 respectively. Conclusion: These results show that the extracts of the whole plant of S. filicaulis possess significant AChE/BuChE inhibitory and antioxidant properties, mostly due to its flavonoid content, suggesting the possible use of the plant in neurodegenerative diseases such as AD.
- Full Text:
- Date Issued: 2019
Antihypertensive effects of the hydroethanol extract of Senecio serratuloides DC in rats
- Tata, Charlotte Mungho, Sewani-Rusike, Constance Rufaro, Oyedeji, Opeoluwa Oyehan, Gwebu, Ephraim Tobela, Mahlakata, Fikile, Nkeh-Chungag, Benedicta Ngwenchi
- Authors: Tata, Charlotte Mungho , Sewani-Rusike, Constance Rufaro , Oyedeji, Opeoluwa Oyehan , Gwebu, Ephraim Tobela , Mahlakata, Fikile , Nkeh-Chungag, Benedicta Ngwenchi
- Date: 2019
- Subjects: South Africa Hypertension Computer File
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/5847 , vital:44656 , https://doi.org/10.1186/s12906-019-2463-2
- Description: Senecio serratuloides DC is used in folk medicine for treating hypertension, skin disorders, internal and external sores, rashes, burns and wounds. This study aimed at investigating the antihypertensive effects of the hydroethanol extract of S. serratuloides (HESS) in N-Nitro-L-arginine methyl ester (L-NAME) induced hypertension in rats. Methods: Acute toxicity of HESS was first determined to provide guidance on doses to be used in this study. Lorke’s method was used to determine safety of the extract in mice. Female Wistar rats were treated orally once daily with L-NAME (40 mg/kg) for 4 weeks and then concomitantly with L-NAME (20 mg/kg) and plant extract (150 and 300 mg/kg), captopril (20 mg/kg) or saline as per assigned group for 2 weeks followed by a 2-week period of assigned treatments only. Blood pressure was monitored weekly. Lipid profile, nitric oxide, renin and angiotensin II concentrations were determined in serum while mineralocorticoid receptor concentration was quantified in the kidney homogenate. Nitric oxide (NO) concentration was determined in serum and cardiac histology performed. Results HESS was found to be non-toxic, having a LD50 greater than 5000 mg/kg. Blood pressure increased progressively in all animals from the second week of L-NAME treatment. HESS treatment significantly and dose-dependently lowered systolic blood pressure (p less 0.001), diastolic blood pressure (p less 0.01), low density lipoprotein cholesterol (p less 0.01) and triglycerides (p less 0.01). It significantly prevented L-NAME induced decrease in serum angiotensin II (p less 0.01), high density lipoprotein cholesterol (p less 0.001) and serum nitric oxide concentrations (p less 0.001). HESS also significantly (p less 0.01) prevented collagen deposition in cardiac tissue. Conclusion The hydro-ethanol extract of Senecio serratuloides showed antihypertensive, antihyperlipidemic and cardioprotective effects in rats thus confirming its usefulness in traditional antihypertensive therapy and potential for antihypertensive drug development.
- Full Text:
- Date Issued: 2019
- Authors: Tata, Charlotte Mungho , Sewani-Rusike, Constance Rufaro , Oyedeji, Opeoluwa Oyehan , Gwebu, Ephraim Tobela , Mahlakata, Fikile , Nkeh-Chungag, Benedicta Ngwenchi
- Date: 2019
- Subjects: South Africa Hypertension Computer File
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/5847 , vital:44656 , https://doi.org/10.1186/s12906-019-2463-2
- Description: Senecio serratuloides DC is used in folk medicine for treating hypertension, skin disorders, internal and external sores, rashes, burns and wounds. This study aimed at investigating the antihypertensive effects of the hydroethanol extract of S. serratuloides (HESS) in N-Nitro-L-arginine methyl ester (L-NAME) induced hypertension in rats. Methods: Acute toxicity of HESS was first determined to provide guidance on doses to be used in this study. Lorke’s method was used to determine safety of the extract in mice. Female Wistar rats were treated orally once daily with L-NAME (40 mg/kg) for 4 weeks and then concomitantly with L-NAME (20 mg/kg) and plant extract (150 and 300 mg/kg), captopril (20 mg/kg) or saline as per assigned group for 2 weeks followed by a 2-week period of assigned treatments only. Blood pressure was monitored weekly. Lipid profile, nitric oxide, renin and angiotensin II concentrations were determined in serum while mineralocorticoid receptor concentration was quantified in the kidney homogenate. Nitric oxide (NO) concentration was determined in serum and cardiac histology performed. Results HESS was found to be non-toxic, having a LD50 greater than 5000 mg/kg. Blood pressure increased progressively in all animals from the second week of L-NAME treatment. HESS treatment significantly and dose-dependently lowered systolic blood pressure (p less 0.001), diastolic blood pressure (p less 0.01), low density lipoprotein cholesterol (p less 0.01) and triglycerides (p less 0.01). It significantly prevented L-NAME induced decrease in serum angiotensin II (p less 0.01), high density lipoprotein cholesterol (p less 0.001) and serum nitric oxide concentrations (p less 0.001). HESS also significantly (p less 0.01) prevented collagen deposition in cardiac tissue. Conclusion The hydro-ethanol extract of Senecio serratuloides showed antihypertensive, antihyperlipidemic and cardioprotective effects in rats thus confirming its usefulness in traditional antihypertensive therapy and potential for antihypertensive drug development.
- Full Text:
- Date Issued: 2019
Antihypertensive effects of the hydroethanol extract of Senecio serratuloides DC in rats
- Tata, Charlotte Mungho, Sewani-Rusike, Constance Rufaro, Oyedeji, Opeoluwa Oyehan, Gwebu, Ephraim Tobela, Mahlakata, Fikile, Nkeh-Chungag, Benedicta Ngwenchi
- Authors: Tata, Charlotte Mungho , Sewani-Rusike, Constance Rufaro , Oyedeji, Opeoluwa Oyehan , Gwebu, Ephraim Tobela , Mahlakata, Fikile , Nkeh-Chungag, Benedicta Ngwenchi
- Date: 2019
- Subjects: South Africa Hypertension Computer File
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/5842 , vital:44654 , https://doi.org/10.1186/s12906-019-2463-2
- Description: Senecio serratuloides DC is used in folk medicine for treating hypertension, skin disorders, internal and external sores, rashes, burns and wounds. This study aimed at investigating the antihypertensive effects of the hydroethanol extract of S. serratuloides (HESS) in N-Nitro-L-arginine methyl ester (L-NAME) induced hypertension in rats. Methods: Acute toxicity of HESS was first determined to provide guidance on doses to be used in this study. Lorke’s method was used to determine safety of the extract in mice. Female Wistar rats were treated orally once daily with L-NAME (40 mg/kg) for 4 weeks and then concomitantly with L-NAME (20 mg/kg) and plant extract (150 and 300 mg/kg), captopril (20 mg/kg) or saline as per assigned group for 2 weeks followed by a 2-week period of assigned treatments only. Blood pressure was monitored weekly. Lipid profile, nitric oxide, renin and angiotensin II concentrations were determined in serum while mineralocorticoid receptor concentration was quantified in the kidney homogenate. Nitric oxide (NO) concentration was determined in serum and cardiac histology performed. Results HESS was found to be non-toxic, having a LD50 greater than 5000 mg/kg. Blood pressure increased progressively in all animals from the second week of L-NAME treatment. HESS treatment significantly and dose-dependently lowered systolic blood pressure (p less 0.001), diastolic blood pressure (p less 0.01), low density lipoprotein cholesterol (p less 0.01) and triglycerides (p less 0.01). It significantly prevented L-NAME induced decrease in serum angiotensin II (p less 0.01), high density lipoprotein cholesterol (p less 0.001) and serum nitric oxide concentrations (p less 0.001). HESS also significantly (p less 0.01) prevented collagen deposition in cardiac tissue. Conclusion The hydro-ethanol extract of Senecio serratuloides showed antihypertensive, antihyperlipidemic and cardioprotective effects in rats thus confirming its usefulness in traditional antihypertensive therapy and potential for antihypertensive drug development.
- Full Text:
- Date Issued: 2019
- Authors: Tata, Charlotte Mungho , Sewani-Rusike, Constance Rufaro , Oyedeji, Opeoluwa Oyehan , Gwebu, Ephraim Tobela , Mahlakata, Fikile , Nkeh-Chungag, Benedicta Ngwenchi
- Date: 2019
- Subjects: South Africa Hypertension Computer File
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/5842 , vital:44654 , https://doi.org/10.1186/s12906-019-2463-2
- Description: Senecio serratuloides DC is used in folk medicine for treating hypertension, skin disorders, internal and external sores, rashes, burns and wounds. This study aimed at investigating the antihypertensive effects of the hydroethanol extract of S. serratuloides (HESS) in N-Nitro-L-arginine methyl ester (L-NAME) induced hypertension in rats. Methods: Acute toxicity of HESS was first determined to provide guidance on doses to be used in this study. Lorke’s method was used to determine safety of the extract in mice. Female Wistar rats were treated orally once daily with L-NAME (40 mg/kg) for 4 weeks and then concomitantly with L-NAME (20 mg/kg) and plant extract (150 and 300 mg/kg), captopril (20 mg/kg) or saline as per assigned group for 2 weeks followed by a 2-week period of assigned treatments only. Blood pressure was monitored weekly. Lipid profile, nitric oxide, renin and angiotensin II concentrations were determined in serum while mineralocorticoid receptor concentration was quantified in the kidney homogenate. Nitric oxide (NO) concentration was determined in serum and cardiac histology performed. Results HESS was found to be non-toxic, having a LD50 greater than 5000 mg/kg. Blood pressure increased progressively in all animals from the second week of L-NAME treatment. HESS treatment significantly and dose-dependently lowered systolic blood pressure (p less 0.001), diastolic blood pressure (p less 0.01), low density lipoprotein cholesterol (p less 0.01) and triglycerides (p less 0.01). It significantly prevented L-NAME induced decrease in serum angiotensin II (p less 0.01), high density lipoprotein cholesterol (p less 0.001) and serum nitric oxide concentrations (p less 0.001). HESS also significantly (p less 0.01) prevented collagen deposition in cardiac tissue. Conclusion The hydro-ethanol extract of Senecio serratuloides showed antihypertensive, antihyperlipidemic and cardioprotective effects in rats thus confirming its usefulness in traditional antihypertensive therapy and potential for antihypertensive drug development.
- Full Text:
- Date Issued: 2019
Antimicrobial resistance awareness program at Settlers Hospital
- Manhanzva, Rufaro Immaculate
- Authors: Manhanzva, Rufaro Immaculate
- Date: 2019
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/97712 , vital:31475
- Description: Expected release date-April 2021
- Full Text: false
- Date Issued: 2019
- Authors: Manhanzva, Rufaro Immaculate
- Date: 2019
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/97712 , vital:31475
- Description: Expected release date-April 2021
- Full Text: false
- Date Issued: 2019
Antiplasmodial Activity of the n-Hexane Extract from Pleurotus ostreatus (Jacq. ex. Fr) P. Kumm
- Afieroho, Ozadheoghene E, Siwe-Noundou, Xavier, Onyia, Chiazor P, Festus, Osamuyi H, Chukwu, Elizabeth C, Adedokun, Olutayo M, Isaacs, Michelle, Hoppe, Heinrich, Krause, Rui W M, Abo, Kio A
- Authors: Afieroho, Ozadheoghene E , Siwe-Noundou, Xavier , Onyia, Chiazor P , Festus, Osamuyi H , Chukwu, Elizabeth C , Adedokun, Olutayo M , Isaacs, Michelle , Hoppe, Heinrich , Krause, Rui W M , Abo, Kio A
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/194981 , vital:45516 , xlink:href="https://doi.org/10.4274/tjps.18894"
- Description: Objectives: Several mushrooms species have been reported to be nematophagous and antiprotozoan. This study reported the antiplasmodial and cytotoxic properties of the n-hexane extract from the edible mushroom Pleurotus ostreatus and the isolation of a sterol from the extract. Materials and Methods: Antiplasmodial and cytotoxicity assays were done in vitro using the plasmodium lactate dehydrogenase assay and human HeLa cervical cell lines, respectively. The structure of the isolated compound from the n-hexane extract was elucidated using spectroscopic techniques. Results: The n-hexane extract (yield: 0.93% w/w) showed dose dependent antiplasmodial activity with the trend in parasite inhibition of: chloroquine (IC50=0.016 μg/mL) > n-hexane extract (IC50=25.18 μg/mL). It also showed mild cytotoxicity (IC50>100 μg/mL; selectivity index >4) compared to the reference drug emetine (IC50=0.013 μg/mL). The known sterol, ergostan-5,7,22-trien-3-ol, was isolated and characterized from the extract. Conclusion: This study reporting for the first time the antiplasmodial activity of P. ostreatus revealed its nutraceutical potential in the management of malaria.
- Full Text:
- Date Issued: 2019
- Authors: Afieroho, Ozadheoghene E , Siwe-Noundou, Xavier , Onyia, Chiazor P , Festus, Osamuyi H , Chukwu, Elizabeth C , Adedokun, Olutayo M , Isaacs, Michelle , Hoppe, Heinrich , Krause, Rui W M , Abo, Kio A
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/194981 , vital:45516 , xlink:href="https://doi.org/10.4274/tjps.18894"
- Description: Objectives: Several mushrooms species have been reported to be nematophagous and antiprotozoan. This study reported the antiplasmodial and cytotoxic properties of the n-hexane extract from the edible mushroom Pleurotus ostreatus and the isolation of a sterol from the extract. Materials and Methods: Antiplasmodial and cytotoxicity assays were done in vitro using the plasmodium lactate dehydrogenase assay and human HeLa cervical cell lines, respectively. The structure of the isolated compound from the n-hexane extract was elucidated using spectroscopic techniques. Results: The n-hexane extract (yield: 0.93% w/w) showed dose dependent antiplasmodial activity with the trend in parasite inhibition of: chloroquine (IC50=0.016 μg/mL) > n-hexane extract (IC50=25.18 μg/mL). It also showed mild cytotoxicity (IC50>100 μg/mL; selectivity index >4) compared to the reference drug emetine (IC50=0.013 μg/mL). The known sterol, ergostan-5,7,22-trien-3-ol, was isolated and characterized from the extract. Conclusion: This study reporting for the first time the antiplasmodial activity of P. ostreatus revealed its nutraceutical potential in the management of malaria.
- Full Text:
- Date Issued: 2019
Application of computational methods in elucidating the isomerization step in the biosynthesis of coumarins
- Authors: Tshiwawa, Tendamudzimu
- Date: 2019
- Subjects: Coumarins , Isomerization , Biosynthesis , Organic compounds -- Synthesis , Cinnamic acid
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/67646 , vital:29124
- Description: The identity of the enzyme(s) responsible for the biosynthetic transformation of cinnamic acid derivatives to important, naturally occurring coumarins has yet to be established. This study constitutes a high-level theoretical analysis of the possibility that a recently reported molecular mechanism of the synthesis of coumarins from Baylis-Hillman adducts, may provide a viable model for three critical phases in the biosynthetic pathway Particular attention has been given to the first of these phases: i) E→Z isomerisation of the cinnamic acid precursor; ii) Cyclisation (lactonisation) to the hemi-acetal intermediate; and ii) Dehydration to afford the coumarin derivative. In order to accomplish this analysis, an enzyme capable, theoretically, of effecting this E→Z isomerisation required identification, and its potential involvement in the transformation mechanism explored. Combined Molecular Mechanics and high-level Quantum Mechanical/DFT calculations were used to access complementary models of appropriate complexes and relevant processes within the enzyme active sites of a range of eleven Chalcone Isomerase (CHI) enzyme candidates, the structures of which were downloaded from the Protein Data Bank. Detailed B3LYP/6-31+G(d,p) calculations have provided pictures of the relative populations of conformations within the ensemble of conformations available at normal temperatures. Conformations of several protonation states of cinnamic acid derivatives have been studied in this way, and the results obtained showed that coupled protonation and deprotonation of (E)-o-coumaric acid provides a viable approach to achieve the E→Z isomerization. In silico docking of the B3LYP/6-31+G(d,p) optimized (E)-o-coumaric acid derivatives in the active sites of each of the candidate CHI enzymes (CHI) revealed that (E)-o-coumaric acid fits well within the active sites of Medicago Sativa CHI crystallographic structures with 1FM8 showing best potential for not only accommodating (E)-o-coumaric acid , but also providing appropriate protein active site residues to effect the simultaneous protonation and deprotonation of the substrate , two residues being optimally placed to facilitate these critical processes. Further exploration of the chemical properties and qualities of selected CHI enzymes, undertaken using High Throughput Virtual Screening (HTVS), confirmed 1FM8 as a viable choice for further studies of the enzyme-catalysed E→Z isomerization of (E)-o-coumaric acid. A molecular dynamics study, performed to further evaluate the evolution of (E)-o-coumaric acid in the CHI active site over time, showed that the ligand in the 1FM8 active site is not only stable, but also that the desired protein-ligand interactions persist throughout the simulation period to facilitate the E→Z isomerization. An integrated molecular orbital and molecular mechanics (ONIOM) study of the 1FM8-(E)-o-coumaric acid complex, involving the direct protonation and deprotonation of the ligand by protein residues; has provided a plausible mechanism for the E → Z isomerization of (E)-o-coumaric acid within the 1FM8 active site; a transition state complex (with an activation energy of ca. 50 kCal.mol-1) has been located and its connection with both the (E)- and (Z)-o-coumaric acid isomer has been confirmed by Intrinsic Reaction Coordinate (IRC) calculations. More realistic models of the 1FM8-(E)-o-coumaric acid complex, with the inclusion of water solvent molecules, have been obtained at both the QM/MM and adaptive QM/MM levels which simulate the dynamic active site at the QM level. The results indicate that the simultaneous protonation and deprotonation of (E)-o-coumaric acid within the CHI enzyme is a water-mediated process – a conclusion consistent with similar reported processes. Visual inspection of the 1FM8-(Z)-o-coumaric acid complex reveals both the necessary orientation of the phenolic and carboxylic acid moieties of the (Z)-o-coumaric acid and the presence of appropriate, proximal active site residues with the potential to permit catalysis of the subsequent lactonisation and dehydration steps required to generate coumarin.
- Full Text:
- Date Issued: 2019
- Authors: Tshiwawa, Tendamudzimu
- Date: 2019
- Subjects: Coumarins , Isomerization , Biosynthesis , Organic compounds -- Synthesis , Cinnamic acid
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/67646 , vital:29124
- Description: The identity of the enzyme(s) responsible for the biosynthetic transformation of cinnamic acid derivatives to important, naturally occurring coumarins has yet to be established. This study constitutes a high-level theoretical analysis of the possibility that a recently reported molecular mechanism of the synthesis of coumarins from Baylis-Hillman adducts, may provide a viable model for three critical phases in the biosynthetic pathway Particular attention has been given to the first of these phases: i) E→Z isomerisation of the cinnamic acid precursor; ii) Cyclisation (lactonisation) to the hemi-acetal intermediate; and ii) Dehydration to afford the coumarin derivative. In order to accomplish this analysis, an enzyme capable, theoretically, of effecting this E→Z isomerisation required identification, and its potential involvement in the transformation mechanism explored. Combined Molecular Mechanics and high-level Quantum Mechanical/DFT calculations were used to access complementary models of appropriate complexes and relevant processes within the enzyme active sites of a range of eleven Chalcone Isomerase (CHI) enzyme candidates, the structures of which were downloaded from the Protein Data Bank. Detailed B3LYP/6-31+G(d,p) calculations have provided pictures of the relative populations of conformations within the ensemble of conformations available at normal temperatures. Conformations of several protonation states of cinnamic acid derivatives have been studied in this way, and the results obtained showed that coupled protonation and deprotonation of (E)-o-coumaric acid provides a viable approach to achieve the E→Z isomerization. In silico docking of the B3LYP/6-31+G(d,p) optimized (E)-o-coumaric acid derivatives in the active sites of each of the candidate CHI enzymes (CHI) revealed that (E)-o-coumaric acid fits well within the active sites of Medicago Sativa CHI crystallographic structures with 1FM8 showing best potential for not only accommodating (E)-o-coumaric acid , but also providing appropriate protein active site residues to effect the simultaneous protonation and deprotonation of the substrate , two residues being optimally placed to facilitate these critical processes. Further exploration of the chemical properties and qualities of selected CHI enzymes, undertaken using High Throughput Virtual Screening (HTVS), confirmed 1FM8 as a viable choice for further studies of the enzyme-catalysed E→Z isomerization of (E)-o-coumaric acid. A molecular dynamics study, performed to further evaluate the evolution of (E)-o-coumaric acid in the CHI active site over time, showed that the ligand in the 1FM8 active site is not only stable, but also that the desired protein-ligand interactions persist throughout the simulation period to facilitate the E→Z isomerization. An integrated molecular orbital and molecular mechanics (ONIOM) study of the 1FM8-(E)-o-coumaric acid complex, involving the direct protonation and deprotonation of the ligand by protein residues; has provided a plausible mechanism for the E → Z isomerization of (E)-o-coumaric acid within the 1FM8 active site; a transition state complex (with an activation energy of ca. 50 kCal.mol-1) has been located and its connection with both the (E)- and (Z)-o-coumaric acid isomer has been confirmed by Intrinsic Reaction Coordinate (IRC) calculations. More realistic models of the 1FM8-(E)-o-coumaric acid complex, with the inclusion of water solvent molecules, have been obtained at both the QM/MM and adaptive QM/MM levels which simulate the dynamic active site at the QM level. The results indicate that the simultaneous protonation and deprotonation of (E)-o-coumaric acid within the CHI enzyme is a water-mediated process – a conclusion consistent with similar reported processes. Visual inspection of the 1FM8-(Z)-o-coumaric acid complex reveals both the necessary orientation of the phenolic and carboxylic acid moieties of the (Z)-o-coumaric acid and the presence of appropriate, proximal active site residues with the potential to permit catalysis of the subsequent lactonisation and dehydration steps required to generate coumarin.
- Full Text:
- Date Issued: 2019
Application of some missing data techniques in estimating missing data in high blood pressure covariates
- Authors: Odeyemi, A. S
- Date: 2019
- Subjects: Missing observations (Statistics) Hypertension
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/15189 , vital:40195
- Description: Cases recorded with high blood pressure are a major concern in both public and private hospitals. Adequate provision of health information of patients relating to high blood pressure in Eastern Cape Hospitals hinges so much on the outcome of statistical analysis results. The usual statistical methodologies become inadequate in handling statistical analysis of data collected due to incomplete patients’ information stored in the hospital database. From time to time, new methods are developed to address the problem of missing data. High blood pressure is linked to a lot of diseases such hypertension, cardiovascular disease, kidney disease and stroke. In this study, we developed a new method for addressing the problem of missing data in assessing model used for estimating missing values in terms of minimum errors(using RMSE, MAE, and SE) and goodness-of-fits(using 2 R and adjusted 2 R ) of this model and P-value. . The study compared six different methods: Original data (OD), Listwise deletion (LD), Mean imputations (MEI), Mean above (MA), and Mean above below(MAB) and two steps nearest neighbour (2-NN).The comparison was performed using original data set, and missing values at 5%, 10%, 20%, 30% were simulated on Framingham risk scores under MCAR and MAR simulation on BMI values given some assumptions. Five performance indicators were used to describe the model minimum errors and goodness of fit for all the methods. The results showed that the 2-NN is the best replacement method at lower levels (5% and10%) of missing values while MA and MEI performed best at higher levels(15% and 20%) of missing values. All comparison was based on estimates closest to those of the original data where no value was missing. MAR results showed that 2-NN performed better than LD,MA,MAB, and MEI at 5%,10%, and 20% levels of missing data in terms of absolute difference in p-value to original data.
- Full Text:
- Date Issued: 2019
- Authors: Odeyemi, A. S
- Date: 2019
- Subjects: Missing observations (Statistics) Hypertension
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/15189 , vital:40195
- Description: Cases recorded with high blood pressure are a major concern in both public and private hospitals. Adequate provision of health information of patients relating to high blood pressure in Eastern Cape Hospitals hinges so much on the outcome of statistical analysis results. The usual statistical methodologies become inadequate in handling statistical analysis of data collected due to incomplete patients’ information stored in the hospital database. From time to time, new methods are developed to address the problem of missing data. High blood pressure is linked to a lot of diseases such hypertension, cardiovascular disease, kidney disease and stroke. In this study, we developed a new method for addressing the problem of missing data in assessing model used for estimating missing values in terms of minimum errors(using RMSE, MAE, and SE) and goodness-of-fits(using 2 R and adjusted 2 R ) of this model and P-value. . The study compared six different methods: Original data (OD), Listwise deletion (LD), Mean imputations (MEI), Mean above (MA), and Mean above below(MAB) and two steps nearest neighbour (2-NN).The comparison was performed using original data set, and missing values at 5%, 10%, 20%, 30% were simulated on Framingham risk scores under MCAR and MAR simulation on BMI values given some assumptions. Five performance indicators were used to describe the model minimum errors and goodness of fit for all the methods. The results showed that the 2-NN is the best replacement method at lower levels (5% and10%) of missing values while MA and MEI performed best at higher levels(15% and 20%) of missing values. All comparison was based on estimates closest to those of the original data where no value was missing. MAR results showed that 2-NN performed better than LD,MA,MAB, and MEI at 5%,10%, and 20% levels of missing data in terms of absolute difference in p-value to original data.
- Full Text:
- Date Issued: 2019
Applications of complex functions on problems in Banach algebras
- Authors: Snyman, Jandré Dillon
- Date: 2019
- Subjects: Banach algebras , Functions of several complex variables
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/48643 , vital:41055
- Description: In this dissertation, we provide applications of complex function theory to problems in Banach algebras. We discuss the structure of analytic functions f : D → A, where D is a domain of C and A is a Banach algebra as given by Aupetit in [3]: either the set {λ ∈ D : Sp(f(λ)) is finite} is of capacity zero, or there exists an integer n such that Sp(f(λ)) has exactly n elements, for every λ, except on a closed, discrete set of capacity zero, where the spectrum has at most n−1 elements. This deep result, which describes the structure of Sp(f(λ)) for all λ ∈ D, relies heavily on subharmonic techniques, which are also included in the dissertation. Let A and B be Banach algebras. A linear mapping φ : A → B is called a Jordan homomorphism if and only if φ(xy + yx) = φ(x)φ(y) + φ(y)φ(x) for every x, y ∈ A. This is equivalent to saying that φ(x 2 ) = φ(x) 2 for every x ∈ A. The following problem, due to I. Kaplansky, is still unsolved for the general Banach algebra case: Let A and B be unital Banach algebras and φ : A → B a unital, invertibility preserving linear mapping. Under what conditions of A and B is φ a Jordan homomorphism? The author’s honours project [24] served as an exposition of the GleasonKahane-Żelazko Theorem [7, Theorem 4], which provides an answer to Kaplansky’s problem in the case where B = C. In this dissertation we look at other special cases of Kaplansky’s problem, such as the case where A and B are von Neumann algberas, as solved by Aupetit [4, Theorem 1.3] and remark that his result holds for the more general case where A is any C ∗ -algebra that has the property that every self-adjoint element is the limit of a sequence of linear combinations of orthogonal idempotents in A, and B is a semi-simple Banach algebra. This result relies heavily on complex function theory, spectral theory and holomorphic functional calculus. We also provide detailed expositions of the work of Taylor [27] in which an operator calculus on undounded, closed linear operators is developed, and the work of Allan [1] in which a holomorphic functional calculus is defined for locally convex algebras.
- Full Text:
- Date Issued: 2019
- Authors: Snyman, Jandré Dillon
- Date: 2019
- Subjects: Banach algebras , Functions of several complex variables
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/48643 , vital:41055
- Description: In this dissertation, we provide applications of complex function theory to problems in Banach algebras. We discuss the structure of analytic functions f : D → A, where D is a domain of C and A is a Banach algebra as given by Aupetit in [3]: either the set {λ ∈ D : Sp(f(λ)) is finite} is of capacity zero, or there exists an integer n such that Sp(f(λ)) has exactly n elements, for every λ, except on a closed, discrete set of capacity zero, where the spectrum has at most n−1 elements. This deep result, which describes the structure of Sp(f(λ)) for all λ ∈ D, relies heavily on subharmonic techniques, which are also included in the dissertation. Let A and B be Banach algebras. A linear mapping φ : A → B is called a Jordan homomorphism if and only if φ(xy + yx) = φ(x)φ(y) + φ(y)φ(x) for every x, y ∈ A. This is equivalent to saying that φ(x 2 ) = φ(x) 2 for every x ∈ A. The following problem, due to I. Kaplansky, is still unsolved for the general Banach algebra case: Let A and B be unital Banach algebras and φ : A → B a unital, invertibility preserving linear mapping. Under what conditions of A and B is φ a Jordan homomorphism? The author’s honours project [24] served as an exposition of the GleasonKahane-Żelazko Theorem [7, Theorem 4], which provides an answer to Kaplansky’s problem in the case where B = C. In this dissertation we look at other special cases of Kaplansky’s problem, such as the case where A and B are von Neumann algberas, as solved by Aupetit [4, Theorem 1.3] and remark that his result holds for the more general case where A is any C ∗ -algebra that has the property that every self-adjoint element is the limit of a sequence of linear combinations of orthogonal idempotents in A, and B is a semi-simple Banach algebra. This result relies heavily on complex function theory, spectral theory and holomorphic functional calculus. We also provide detailed expositions of the work of Taylor [27] in which an operator calculus on undounded, closed linear operators is developed, and the work of Allan [1] in which a holomorphic functional calculus is defined for locally convex algebras.
- Full Text:
- Date Issued: 2019
Applying anthropological perspectives in criminal procedures involving murder in Port Elizabeth, 2000-2016
- Authors: Thornton, Jessica Leigh
- Date: 2019
- Subjects: Criminal procedures
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/44688 , vital:38161
- Description: With the spike of annual reported murders in South Africa, the country is continuing to climb the global rank of the world’s most violent countries. In 2016 alone, there were over nineteen thousand reported murders, equalling over fifty murders per day, with the Eastern Cape holding position as the province with the highest murder rate. Studies indicate that Port Elizabeth is the hardest hit by crime, adding up to 60% of all reported crimes in the province and despite the use of a ‘catch and convict’ only approach in criminal proceedings, violence and crime are still highly prevalent. Thus, overall the situation suggests that it may be beyond law enforcement control and even though the South African Police Service have taken some progressive steps in reforming procedures, generally, these have been too little and too late, as the reforms introduced are piecemeal and crisis driven. This thesis, therefore, proposes that additional approaches may be needed to improve investigations of the most pernicious crimes. Here, the focus is on the role of culture and social life in ‘murder-scapes’ with a critical contribution of the ‘habitus’ of murder allowing for the meaningful engagement with criminal acts, policing, sentencing, imprisonment and probation. In this regard, perspectives drawn from anthropology can possibly assist law enforcement officials in their steps of investigating a murder by providing a more ethnographic, holistic and integrated narrative in all areas of a criminal proceeding. An efficacious and constructive interpretation of the different subcultures crime scene processing, profiles development, testimony documentation and participation production with the police force and task teams can assist in redirecting and reappraising current practises that prove incompetent. That is, in attempting to review the current procedures conducted by law enforcers to identify how and where anthropological and ethnographical knowledge can be applied and successfully utilised, an assessment may aid officials in better investigative practises which could have implications for wider lenses making use of action, investigation, containment, prevention and rehabilitation. By advancing a deep understanding of the issue of murder in the South African context, implications for a wider, equally modernising and equally troubled society in the global South can be inferred.
- Full Text:
- Date Issued: 2019
- Authors: Thornton, Jessica Leigh
- Date: 2019
- Subjects: Criminal procedures
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/44688 , vital:38161
- Description: With the spike of annual reported murders in South Africa, the country is continuing to climb the global rank of the world’s most violent countries. In 2016 alone, there were over nineteen thousand reported murders, equalling over fifty murders per day, with the Eastern Cape holding position as the province with the highest murder rate. Studies indicate that Port Elizabeth is the hardest hit by crime, adding up to 60% of all reported crimes in the province and despite the use of a ‘catch and convict’ only approach in criminal proceedings, violence and crime are still highly prevalent. Thus, overall the situation suggests that it may be beyond law enforcement control and even though the South African Police Service have taken some progressive steps in reforming procedures, generally, these have been too little and too late, as the reforms introduced are piecemeal and crisis driven. This thesis, therefore, proposes that additional approaches may be needed to improve investigations of the most pernicious crimes. Here, the focus is on the role of culture and social life in ‘murder-scapes’ with a critical contribution of the ‘habitus’ of murder allowing for the meaningful engagement with criminal acts, policing, sentencing, imprisonment and probation. In this regard, perspectives drawn from anthropology can possibly assist law enforcement officials in their steps of investigating a murder by providing a more ethnographic, holistic and integrated narrative in all areas of a criminal proceeding. An efficacious and constructive interpretation of the different subcultures crime scene processing, profiles development, testimony documentation and participation production with the police force and task teams can assist in redirecting and reappraising current practises that prove incompetent. That is, in attempting to review the current procedures conducted by law enforcers to identify how and where anthropological and ethnographical knowledge can be applied and successfully utilised, an assessment may aid officials in better investigative practises which could have implications for wider lenses making use of action, investigation, containment, prevention and rehabilitation. By advancing a deep understanding of the issue of murder in the South African context, implications for a wider, equally modernising and equally troubled society in the global South can be inferred.
- Full Text:
- Date Issued: 2019
Applying anthropological perspectives in criminal procedures involving murder in Port Elizabeth, 2000-2016
- Authors: Thornton, Jessica Leigh
- Date: 2019
- Subjects: Murder -- South Africa -- Port Elizabeth , Crime -- South Africa -- Port Elizabeth Law enforcement -- South Africa -- Port Elizabeth Criminology -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/45238 , vital:38335
- Description: With the spike of annual reported murders in South Africa, the country is continuing to climb the global rank of the world’s most violent countries. In 2016 alone, there were over nineteen thousand reported murders, equalling over fifty murders per day, with the Eastern Cape holding position as the province with the highest murder rate. Studies indicate that Port Elizabeth is the hardest hit by crime, adding up to 60% of all reported crimes in the province and despite the use of a ‘catch and convict’ only approach in criminal proceedings, violence and crime are still highly prevalent. Thus, overall the situation suggests that it may be beyond law enforcement control and even though the South African Police Service have taken some progressive steps in reforming procedures, generally, these have been too little and too late, as the reforms introduced are piecemeal and crisis driven. This thesis, therefore, proposes that additional approaches may be needed to improve investigations of the most pernicious crimes. Here, the focus is on the role of culture and social life in ‘murder-scapes’ with a critical contribution of the ‘habitus’ of murder allowing for the meaningful engagement with criminal acts, policing, sentencing, imprisonment and probation. In this regard, perspectives drawn from anthropology can possibly assist law enforcement officials in their steps of investigating a murder by providing a more ethnographic, holistic and integrated narrative in all areas of a criminal proceeding. An efficacious and constructive interpretation of the different subcultures, crime scene processing, profiles development, testimony documentation and participation production with the police force and task teams can assist in redirecting and reappraising current practises that prove incompetent. That is, in attempting to review the current procedures conducted by law enforcers to identify how and where anthropological and ethnographical knowledge can be applied and successfully utilised, an assessment may aid officials in better investigative practises which could have implications for wider lenses making use of action, investigation, containment, prevention and rehabilitation. By advancing a deep understanding of the issue of murder in the South African context, implications for a wider, equally modernising and equally troubled society in the global South can be inferred.
- Full Text:
- Date Issued: 2019
- Authors: Thornton, Jessica Leigh
- Date: 2019
- Subjects: Murder -- South Africa -- Port Elizabeth , Crime -- South Africa -- Port Elizabeth Law enforcement -- South Africa -- Port Elizabeth Criminology -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/45238 , vital:38335
- Description: With the spike of annual reported murders in South Africa, the country is continuing to climb the global rank of the world’s most violent countries. In 2016 alone, there were over nineteen thousand reported murders, equalling over fifty murders per day, with the Eastern Cape holding position as the province with the highest murder rate. Studies indicate that Port Elizabeth is the hardest hit by crime, adding up to 60% of all reported crimes in the province and despite the use of a ‘catch and convict’ only approach in criminal proceedings, violence and crime are still highly prevalent. Thus, overall the situation suggests that it may be beyond law enforcement control and even though the South African Police Service have taken some progressive steps in reforming procedures, generally, these have been too little and too late, as the reforms introduced are piecemeal and crisis driven. This thesis, therefore, proposes that additional approaches may be needed to improve investigations of the most pernicious crimes. Here, the focus is on the role of culture and social life in ‘murder-scapes’ with a critical contribution of the ‘habitus’ of murder allowing for the meaningful engagement with criminal acts, policing, sentencing, imprisonment and probation. In this regard, perspectives drawn from anthropology can possibly assist law enforcement officials in their steps of investigating a murder by providing a more ethnographic, holistic and integrated narrative in all areas of a criminal proceeding. An efficacious and constructive interpretation of the different subcultures, crime scene processing, profiles development, testimony documentation and participation production with the police force and task teams can assist in redirecting and reappraising current practises that prove incompetent. That is, in attempting to review the current procedures conducted by law enforcers to identify how and where anthropological and ethnographical knowledge can be applied and successfully utilised, an assessment may aid officials in better investigative practises which could have implications for wider lenses making use of action, investigation, containment, prevention and rehabilitation. By advancing a deep understanding of the issue of murder in the South African context, implications for a wider, equally modernising and equally troubled society in the global South can be inferred.
- Full Text:
- Date Issued: 2019
Applying distributed ledger technology to digital evidence integrity
- Weilbach, William T, Motara, Yusuf, M
- Authors: Weilbach, William T , Motara, Yusuf, M
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428960 , vital:72549 , https://ieeexplore.ieee.org/abstract/document/8732798
- Description: This paper examines the way in which blockchain technology can be used to improve the verification of integrity of evidence in digital forensics. Some background into digital forensic practices and blockchain technology are discussed to provide necessary context. A particular scalable method of verifying point-in-time existence of a piece of digital evidence, using the OpenTimestamps (OTS) service, is described, and tests are carried out to independently validate the claims made by the service. The results demonstrate that the OTS service is highly reliable with a zero false positive and false negative error rate for timestamp attestations, but that it is not suitable for timesensitive timestamping due to the variance of the accuracy of timestamps induced by block confirmation times in the Bitcoin blockchain.
- Full Text:
- Date Issued: 2019
- Authors: Weilbach, William T , Motara, Yusuf, M
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428960 , vital:72549 , https://ieeexplore.ieee.org/abstract/document/8732798
- Description: This paper examines the way in which blockchain technology can be used to improve the verification of integrity of evidence in digital forensics. Some background into digital forensic practices and blockchain technology are discussed to provide necessary context. A particular scalable method of verifying point-in-time existence of a piece of digital evidence, using the OpenTimestamps (OTS) service, is described, and tests are carried out to independently validate the claims made by the service. The results demonstrate that the OTS service is highly reliable with a zero false positive and false negative error rate for timestamp attestations, but that it is not suitable for timesensitive timestamping due to the variance of the accuracy of timestamps induced by block confirmation times in the Bitcoin blockchain.
- Full Text:
- Date Issued: 2019
Arbuscular mycorrhizal fungi as a bio-indicator of soil health under agricultural management practices in South Africa
- Authors: Sekgota, Wendy Maphefo
- Date: 2019
- Subjects: Soils -- Quality -- South Africa , Soil fertility -- South Africa , Fungi in agriculture -- South Africa , Mycorrhizal fungi , Vesicular-arbuscular mycorrhizas , Fungi -- Spores , Soils -- Agricultural chemical content
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/72161 , vital:30011
- Description: This study investigated the activity of arbuscular mycorrhizal (AM) fungi as a potential biological indicator of soil health under conventional and conservation agricultural management in South Africa. An experimental trial consisting of three replicates plots under conventional and reduced tillage subdivided into twelve treatments of six crops and two fertilizer inputs was assessed over four growing seasons for various AM fungal parameters such as spore density, most probable number (MPN) of propagules percentage root colonisation and easily extractable glomalin (EEG). Cropping combinations were maize monoculture; maize soybean rotation; maize cowpea rotation; maize cowpea intercropping; maize oats intercropping and maize vetch intercropping. Resident AM fungal spore numbers and EEG protein levels were very low and no root colonization was recorded in the first two growing seasons. These findings prompted the need for the inoculation of the study site in the third growing season with a commercial AM fungal product (MycorootTM). Spore numbers, EEG concentrations and percentage root colonisation increased 8 weeks after inoculation but were significantly reduced in the fourth growing season that was not inoculated. MPN infectivity increased with inoculation particularly under conventional tillage and maize monoculture. Resident spore taxa were morphologically identified into three genera Gigaspora, Scutellospora, and Glomus. For the first two growing seasons, the maize roots were heavily colonized by a pathogenic fungus after mycorrhizal inoculation no evidence of pathogenic fungi was observed. In the fourth growing season which did not receive inoculation, root colonization started to decline. Reduced tillage, high fertilizer input combined with maize cowpea rotation (MC) and maize hairy vetch intercropping (Mv) had a significant effect (P = 0.01) on AM fungal spore numbers. Cropping systems and high fertilizer input had a significant effect on EEG concentrations in the second growing season. Overall, fertilizer application and crop type had implications for mycorrhizal activity. The soil health status in this study site was deemed low as measured by the impaired mycorrhizal activity due to agricultural management practices. Field inoculation combined with classical and molecular tools could provide a more realistic assessment of the effect of agricultural management practices on AM fungi as potential bioindicators of soil health. Therefore, AM fungi could be used as bioindicators of soil health under agricultural management practices in South African soil conditions.
- Full Text:
- Date Issued: 2019
- Authors: Sekgota, Wendy Maphefo
- Date: 2019
- Subjects: Soils -- Quality -- South Africa , Soil fertility -- South Africa , Fungi in agriculture -- South Africa , Mycorrhizal fungi , Vesicular-arbuscular mycorrhizas , Fungi -- Spores , Soils -- Agricultural chemical content
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/72161 , vital:30011
- Description: This study investigated the activity of arbuscular mycorrhizal (AM) fungi as a potential biological indicator of soil health under conventional and conservation agricultural management in South Africa. An experimental trial consisting of three replicates plots under conventional and reduced tillage subdivided into twelve treatments of six crops and two fertilizer inputs was assessed over four growing seasons for various AM fungal parameters such as spore density, most probable number (MPN) of propagules percentage root colonisation and easily extractable glomalin (EEG). Cropping combinations were maize monoculture; maize soybean rotation; maize cowpea rotation; maize cowpea intercropping; maize oats intercropping and maize vetch intercropping. Resident AM fungal spore numbers and EEG protein levels were very low and no root colonization was recorded in the first two growing seasons. These findings prompted the need for the inoculation of the study site in the third growing season with a commercial AM fungal product (MycorootTM). Spore numbers, EEG concentrations and percentage root colonisation increased 8 weeks after inoculation but were significantly reduced in the fourth growing season that was not inoculated. MPN infectivity increased with inoculation particularly under conventional tillage and maize monoculture. Resident spore taxa were morphologically identified into three genera Gigaspora, Scutellospora, and Glomus. For the first two growing seasons, the maize roots were heavily colonized by a pathogenic fungus after mycorrhizal inoculation no evidence of pathogenic fungi was observed. In the fourth growing season which did not receive inoculation, root colonization started to decline. Reduced tillage, high fertilizer input combined with maize cowpea rotation (MC) and maize hairy vetch intercropping (Mv) had a significant effect (P = 0.01) on AM fungal spore numbers. Cropping systems and high fertilizer input had a significant effect on EEG concentrations in the second growing season. Overall, fertilizer application and crop type had implications for mycorrhizal activity. The soil health status in this study site was deemed low as measured by the impaired mycorrhizal activity due to agricultural management practices. Field inoculation combined with classical and molecular tools could provide a more realistic assessment of the effect of agricultural management practices on AM fungi as potential bioindicators of soil health. Therefore, AM fungi could be used as bioindicators of soil health under agricultural management practices in South African soil conditions.
- Full Text:
- Date Issued: 2019
Archives and Records Management Programmes in selected Universities in South Africa: A Study of University of Fort Hare and Rhodes University
- Authors: Somniso, Zoleka
- Date: 2019
- Subjects: Records -- Management
- Language: English
- Type: Thesis , Masters , MSoc. Sci (Library and information science)
- Identifier: http://hdl.handle.net/10353/18280 , vital:42248
- Description: The study investigates the Archives and Records Management Programmes (ARMP) in the University of Fort Hare (UFH) and Rhodes University (RU). The task of managing huge quantities of records and archives material is not an easy task when people have to use limited resources. The Research Objectives of the this study was to find out types of records created, received and maintained by university archives and records management programmes at University of Fort Hare and Rhodes University. Establish the available infrastructure for ARMP at the UFH and RU. Find out the legislative and regulatory frameworks that govern the ARMP at the UFH and RU. Identify challenges if there are any facing ARMP at the UFH and Rhodes University. Interviews and questionnaires were two research instruments used in this study to collect data; additional data was collected by reading relevant documents gathered on both institutions and on their website. In this study, the sample was 26 respondents from both universities. The study dealt with administrative staff who deal with records management: Records managers/Officers and Archivists at both institutions. viii Data collected was coded and analysed using Statistical Package for Social Sciences (SPSS) and the findings were presented using pie chart , graphs. The triangulation approaches involves using more than one method to collect data and it is a way of assuring the validity of research with variety of methods to collect data. Findings revealed that respondents were unaware of ARMP in the university. And also some of the findings were the infrastructural needs such as the Lack of records storage, space, Records Preservation facilities (RH, Light), Personnel Training and Development. The challenges facing ARMP in universities includes: a lack of programmes to manage records and archives material, absence of policy that regulates archives and records keeping in the universities understudy, the existing infrastructure at hand cannot meet the requirements for regulatory framework on records and archives management. Based on these challenges mentioned above, the study recommended that both institutions should improve their infrastructure as to be able to preserve the archival material. Training and retraining of staff among others should include use of technology, filing, records creation, maintenance and disposition
- Full Text:
- Date Issued: 2019
- Authors: Somniso, Zoleka
- Date: 2019
- Subjects: Records -- Management
- Language: English
- Type: Thesis , Masters , MSoc. Sci (Library and information science)
- Identifier: http://hdl.handle.net/10353/18280 , vital:42248
- Description: The study investigates the Archives and Records Management Programmes (ARMP) in the University of Fort Hare (UFH) and Rhodes University (RU). The task of managing huge quantities of records and archives material is not an easy task when people have to use limited resources. The Research Objectives of the this study was to find out types of records created, received and maintained by university archives and records management programmes at University of Fort Hare and Rhodes University. Establish the available infrastructure for ARMP at the UFH and RU. Find out the legislative and regulatory frameworks that govern the ARMP at the UFH and RU. Identify challenges if there are any facing ARMP at the UFH and Rhodes University. Interviews and questionnaires were two research instruments used in this study to collect data; additional data was collected by reading relevant documents gathered on both institutions and on their website. In this study, the sample was 26 respondents from both universities. The study dealt with administrative staff who deal with records management: Records managers/Officers and Archivists at both institutions. viii Data collected was coded and analysed using Statistical Package for Social Sciences (SPSS) and the findings were presented using pie chart , graphs. The triangulation approaches involves using more than one method to collect data and it is a way of assuring the validity of research with variety of methods to collect data. Findings revealed that respondents were unaware of ARMP in the university. And also some of the findings were the infrastructural needs such as the Lack of records storage, space, Records Preservation facilities (RH, Light), Personnel Training and Development. The challenges facing ARMP in universities includes: a lack of programmes to manage records and archives material, absence of policy that regulates archives and records keeping in the universities understudy, the existing infrastructure at hand cannot meet the requirements for regulatory framework on records and archives management. Based on these challenges mentioned above, the study recommended that both institutions should improve their infrastructure as to be able to preserve the archival material. Training and retraining of staff among others should include use of technology, filing, records creation, maintenance and disposition
- Full Text:
- Date Issued: 2019
Assessing flood vulnerability in the Nelson Mandela Bay Metro
- Authors: Zuze, Hillary
- Date: 2019
- Subjects: Floods -- South Africa -- Nelson Mandela Bay Municipality , Natural disasters Hazardous geographic environments Hazardous geographic environments -- Risk assessment , Climatic changes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/44224 , vital:37135
- Description: Floods are the most frequent amongst all global natural disasters at present, causing problems such as bridge collapses, fatalities, building damages and traffic delays. Between 1995 and 2015, there were approximately 3062 global flood disasters which accounted for 56% of all declared natural disasters and these affected 2.3 billion people (almost a third of the world’s population at the time) (EMDAT, 2015). The cost of damages for this period incurred for buildings and other infrastructure was at an all-time high of R23.69 (US$1.891) trillion. It is postulated through various studies that the number of urban flood events reported is increasing significantly in comparison to the previous decades (Armah et al., 2010; Lóczy, 2013; Leaning and Guha-Sapir, 2013; EMDAT, 2015; Tanoue et al., 2016; Rogger et al., 2017). Some research has also noted an increase in the number of floods per year, which has ascended to an average of 171 in this decade, from an annual average of 127 in the previous one (Dozier, 2013; Guha Sapir et al., 2016). Sources such as the Centre of Research and Epidemiological Disasters (Guha Sapir et al., 2016) recorded that from 1995 to 2015, globally, millions of homes were vulnerable to weather-related disasters, along with 130,000 health and education facilities. During this period, urban floods accounted for 98% of houses damaged and 99.9% of education and health facilities demolished by a weather-related disaster (Davies, 2017). Flooding is particularly harmful in terms of fatalities in developing countries due to inadequate flood protection and mitigation measures (Di Baldassarre et al., 2010; Dozier, 2013). Some studies attribute the high fatalities in developing countries to the inadequate disaster management strategies implemented to counter the impacts of urban flooding (Egbinola et al., 2015; Pazzi et al., 2016; Mavhura et al., 2017). Other authors have attributed the high fatalities to the sheer number of people residing in areas prone to flooding, which has been the knock-on effect of rapidly expanding cities, overwhelmed government agencies, and a pre-existing political and social system that promotes marginalisation (Collins, 2008; Aboagye, 2012). The occupation of flood-prone areas by settlements, which is a common feature in developing countries, is the major contributor to the fatalities as it involves a degree of risk. Risk is exposure to an undesired event, in this case flooding, and contributes directly to differing levels of vulnerability (Samuels, 2018). Communities have differing perceptions of flood vulnerability because of a combination of factors. These include the magnitude of the flood experienced, the number of people or the value of assets potentially affected by flooding due to location, and the lack of socioeconomic capacity to do anything to alter their vulnerability to a disaster (Hall et al., 2005; Adger, 2006; Birkmann et al., 2013; Rogger et al., 2017). Some communities acknowledge that there are people residing in flood prone areas and take measures to reduce or eliminate the risk through social, political and economic networks. In other cases, communities are able to identify their exposure to flooding but do not have the capacity to reduce the effects (Bouchard et al., 2007; Agbaoye, 2012; Musungu et al., 2012; Siyongwana, Heijne, and Tele et al., 20155).
- Full Text:
- Date Issued: 2019
- Authors: Zuze, Hillary
- Date: 2019
- Subjects: Floods -- South Africa -- Nelson Mandela Bay Municipality , Natural disasters Hazardous geographic environments Hazardous geographic environments -- Risk assessment , Climatic changes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/44224 , vital:37135
- Description: Floods are the most frequent amongst all global natural disasters at present, causing problems such as bridge collapses, fatalities, building damages and traffic delays. Between 1995 and 2015, there were approximately 3062 global flood disasters which accounted for 56% of all declared natural disasters and these affected 2.3 billion people (almost a third of the world’s population at the time) (EMDAT, 2015). The cost of damages for this period incurred for buildings and other infrastructure was at an all-time high of R23.69 (US$1.891) trillion. It is postulated through various studies that the number of urban flood events reported is increasing significantly in comparison to the previous decades (Armah et al., 2010; Lóczy, 2013; Leaning and Guha-Sapir, 2013; EMDAT, 2015; Tanoue et al., 2016; Rogger et al., 2017). Some research has also noted an increase in the number of floods per year, which has ascended to an average of 171 in this decade, from an annual average of 127 in the previous one (Dozier, 2013; Guha Sapir et al., 2016). Sources such as the Centre of Research and Epidemiological Disasters (Guha Sapir et al., 2016) recorded that from 1995 to 2015, globally, millions of homes were vulnerable to weather-related disasters, along with 130,000 health and education facilities. During this period, urban floods accounted for 98% of houses damaged and 99.9% of education and health facilities demolished by a weather-related disaster (Davies, 2017). Flooding is particularly harmful in terms of fatalities in developing countries due to inadequate flood protection and mitigation measures (Di Baldassarre et al., 2010; Dozier, 2013). Some studies attribute the high fatalities in developing countries to the inadequate disaster management strategies implemented to counter the impacts of urban flooding (Egbinola et al., 2015; Pazzi et al., 2016; Mavhura et al., 2017). Other authors have attributed the high fatalities to the sheer number of people residing in areas prone to flooding, which has been the knock-on effect of rapidly expanding cities, overwhelmed government agencies, and a pre-existing political and social system that promotes marginalisation (Collins, 2008; Aboagye, 2012). The occupation of flood-prone areas by settlements, which is a common feature in developing countries, is the major contributor to the fatalities as it involves a degree of risk. Risk is exposure to an undesired event, in this case flooding, and contributes directly to differing levels of vulnerability (Samuels, 2018). Communities have differing perceptions of flood vulnerability because of a combination of factors. These include the magnitude of the flood experienced, the number of people or the value of assets potentially affected by flooding due to location, and the lack of socioeconomic capacity to do anything to alter their vulnerability to a disaster (Hall et al., 2005; Adger, 2006; Birkmann et al., 2013; Rogger et al., 2017). Some communities acknowledge that there are people residing in flood prone areas and take measures to reduce or eliminate the risk through social, political and economic networks. In other cases, communities are able to identify their exposure to flooding but do not have the capacity to reduce the effects (Bouchard et al., 2007; Agbaoye, 2012; Musungu et al., 2012; Siyongwana, Heijne, and Tele et al., 20155).
- Full Text:
- Date Issued: 2019
Assessing household food insecurity experience in the context of deforestation in Cameroon
- Ngome, Precillia I T, Shackleton, Charlie M, Degrande, Ann, Nossi, Eric J, Ngome, Francis
- Authors: Ngome, Precillia I T , Shackleton, Charlie M , Degrande, Ann , Nossi, Eric J , Ngome, Francis
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/398180 , vital:69382 , xlink:href="https://doi.org/10.1016/j.foodpol.2019.02.003"
- Full Text:
- Date Issued: 2019
- Authors: Ngome, Precillia I T , Shackleton, Charlie M , Degrande, Ann , Nossi, Eric J , Ngome, Francis
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/398180 , vital:69382 , xlink:href="https://doi.org/10.1016/j.foodpol.2019.02.003"
- Full Text:
- Date Issued: 2019
Assessing in-vivo clearance of colorectal cancer-targeting peptide-functionalized gold nanoparticles
- Authors: Xakaza, Hlumisa Belinda
- Date: 2019
- Subjects: Nanoparticles , Gold Nanotechnology -- Health aspects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/44323 , vital:37153
- Description: Colorectal cancer (CRC) is a major public health problem. Gold nanoparticles (AuNPs) have been proved as a possible diagnostic tool to target CRC by peptides conjugated to gold nanoparticles (p-AuNP). According to previous reports, AuNPs accumulate in internal organs and have raised serious concerns on toxicity and safety. Understanding their fate in the body and the physiology underlying their clearance is crucial for toxicological evaluation and clinical translations. Six groups of rats were intravenously injected with a single dose of 100μg/kg body weight of citrate-capped (c.c-AuNPs), PEG-coated (PEG-AuNPs), and peptide functionalized gold nanoparticles (p.L-AuNPs, p.C-AuNPs, and p.14-AuNPs), to assess their physiologic clearance over a short-term (over sequential time-points: day 1, 3, 5, 7 and 14) and long-term period (three months). The inductively coupled optical-electron spectrometry (ICP-OES) showed accumulated c.c-AuNPs in the liver tissue. Moreover, a rapid and decreasing pattern of concentration of AuNPs was observed in urine and feces, with total excretion at day 7. Elevated levels of urine urea nitrogen (UUN) and urine creatinine (UCREA) reported an impaired kidney function for the c.c-AuNP group, while H&E staining indicated chronic progressive nephropathy (CPN) in all groups, 3 months post-injection, which is in all probability related to aging. Signs of inflammation were observed in rats treated with c.c-AuNPs, 2 weeks post-injection. The overall findings showed that the clearance of c.c-AuNPs’ clearance is compromised, which can have side-effects, while the excretion profiles of the p-AuNPs were consistent with the reducing long-term retention in the excretory organs. The p-AuNPs were found to be non-toxic and therefore show promise for CRC diagnostics and therapeutic purposes.
- Full Text:
- Date Issued: 2019
Assessing in-vivo clearance of colorectal cancer-targeting peptide-functionalized gold nanoparticles
- Authors: Xakaza, Hlumisa Belinda
- Date: 2019
- Subjects: Nanoparticles , Gold Nanotechnology -- Health aspects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/44323 , vital:37153
- Description: Colorectal cancer (CRC) is a major public health problem. Gold nanoparticles (AuNPs) have been proved as a possible diagnostic tool to target CRC by peptides conjugated to gold nanoparticles (p-AuNP). According to previous reports, AuNPs accumulate in internal organs and have raised serious concerns on toxicity and safety. Understanding their fate in the body and the physiology underlying their clearance is crucial for toxicological evaluation and clinical translations. Six groups of rats were intravenously injected with a single dose of 100μg/kg body weight of citrate-capped (c.c-AuNPs), PEG-coated (PEG-AuNPs), and peptide functionalized gold nanoparticles (p.L-AuNPs, p.C-AuNPs, and p.14-AuNPs), to assess their physiologic clearance over a short-term (over sequential time-points: day 1, 3, 5, 7 and 14) and long-term period (three months). The inductively coupled optical-electron spectrometry (ICP-OES) showed accumulated c.c-AuNPs in the liver tissue. Moreover, a rapid and decreasing pattern of concentration of AuNPs was observed in urine and feces, with total excretion at day 7. Elevated levels of urine urea nitrogen (UUN) and urine creatinine (UCREA) reported an impaired kidney function for the c.c-AuNP group, while H&E staining indicated chronic progressive nephropathy (CPN) in all groups, 3 months post-injection, which is in all probability related to aging. Signs of inflammation were observed in rats treated with c.c-AuNPs, 2 weeks post-injection. The overall findings showed that the clearance of c.c-AuNPs’ clearance is compromised, which can have side-effects, while the excretion profiles of the p-AuNPs were consistent with the reducing long-term retention in the excretory organs. The p-AuNPs were found to be non-toxic and therefore show promise for CRC diagnostics and therapeutic purposes.
- Full Text:
- Date Issued: 2019
Assessing teaching capacity of novice teachers through mentoring in primary schools.
- Authors: Mthi,Tanduxolo Nicholas
- Date: 2019
- Subjects: Mentoring in education Teachers -- In-service training
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10353/16566 , vital:40732
- Description: The quality of teacher education seems to have become a crucial point of debate worldwide. However, teaching seems to be one of the careers without a recognised apprenticeship. Therefore, mentoring has been seen as an appropriate way for experienced teachers to guide, assist, coach and motivate teachers in their teaching capacity. Teaching capacity is described as having a broad content which can be related to quality teaching, teacher effectiveness and teacher behaviour in the classroom or in the school. The lens with which the study was viewed was through Lave and Wenger’s (1998) theory, Community of Practice (CoP). Community of Practice is defined as a process of social learning that occurs when people who have a common interest in a subject or area collaborate over an extended period of time, sharing ideas and strategies, determining solutions and building innovations. The study used mixed methods and concurrent triangulation design in sampling 60 participants for quantitative data and 6 participants for qualitative data. The unit of analysis were novice teachers who were randomly and purposively selected. Data gathering methods included questionnaires, classroom observations and document analysis. The focus was on the primary schools, Foundation Phase (FP) novice teachers. The findings revealed utilisation of different mentoring approaches such as one on one; Foundation Phase Team and school- based mentoring. Although the study reveals that the work of the mentor teachers and novice teachers has evolved to include Learning Teams to improve the teaching capacity of teachers; some mentoring approaches were less effective. The study suggests, therefore, that schoolbased and district-based mentoring programmes to be formally organised as part of developing novice teachers’ teaching capacity.
- Full Text:
- Date Issued: 2019
- Authors: Mthi,Tanduxolo Nicholas
- Date: 2019
- Subjects: Mentoring in education Teachers -- In-service training
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10353/16566 , vital:40732
- Description: The quality of teacher education seems to have become a crucial point of debate worldwide. However, teaching seems to be one of the careers without a recognised apprenticeship. Therefore, mentoring has been seen as an appropriate way for experienced teachers to guide, assist, coach and motivate teachers in their teaching capacity. Teaching capacity is described as having a broad content which can be related to quality teaching, teacher effectiveness and teacher behaviour in the classroom or in the school. The lens with which the study was viewed was through Lave and Wenger’s (1998) theory, Community of Practice (CoP). Community of Practice is defined as a process of social learning that occurs when people who have a common interest in a subject or area collaborate over an extended period of time, sharing ideas and strategies, determining solutions and building innovations. The study used mixed methods and concurrent triangulation design in sampling 60 participants for quantitative data and 6 participants for qualitative data. The unit of analysis were novice teachers who were randomly and purposively selected. Data gathering methods included questionnaires, classroom observations and document analysis. The focus was on the primary schools, Foundation Phase (FP) novice teachers. The findings revealed utilisation of different mentoring approaches such as one on one; Foundation Phase Team and school- based mentoring. Although the study reveals that the work of the mentor teachers and novice teachers has evolved to include Learning Teams to improve the teaching capacity of teachers; some mentoring approaches were less effective. The study suggests, therefore, that schoolbased and district-based mentoring programmes to be formally organised as part of developing novice teachers’ teaching capacity.
- Full Text:
- Date Issued: 2019
Assessing the abundance of non-timber forest products in relation to forest succession on the Wild Coast, South Africa
- Authors: Njwaxu, Afika
- Date: 2019
- Subjects: Non-timber forest products -- South Africa -- Eastern Cape , Forest ecology -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Non-timber forest products -- South Africa -- Willowvale , Forest ecology -- South Africa -- Willowvale , Rural development -- South Africa -- Willowvale , Forest plants -- South Africa -- Eastern Cape
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/94090 , vital:30999
- Description: The number of people in the Eastern Cape, South Africa, that are engaging in arable cropping has declined markedly over the last few decades. This is due to a number of factors such as a decrease in human capital because of migration of able-bodied people to urban areas, disinclination to participate in farming, raiding of crops by livestock and lack of equipment. This has resulted in abandoned croplands being invaded by trees and shrubs as the start of forest succession leading to a change in species composition and the ecosystem benefits reaped from these sites. Key amongst these benefits is a variety of non-timber forests products (NTFPs) which are an integral part of livelihoods in the area. The study was conducted in Willowvale, on the Wild Coast, South Africa. Aerial photographs were used to determine when cessation of cropping occurred in local fields and when revegetation began in order to determine the age of old fields. Botanical inventory and Braun-Blanquet scale were used to assess species richness, composition and abundance of vegetation in fields abandoned at different times. Focus groups were used to identify NTFPs found in these old fields, their uses as well as rank their importance to the local people. Results showed an increase in woody cover with time since field abandonment. Species richness also increased with age of the old field with approximately three species gained per decade. When species richness was disaggregated by growth forms, herbaceous plants were abundant in the early stages of succession, shrubs in the mature stages and trees increased steadily with time. A total of 177 species were recorded from 50 plots that were sampled during the ecological data collection. Of these, 70 species (39.6%) were identified by the focus group participants as NTFPs. The participants grouped the NTFPs into six categories namely: food, building, medicinal, craft, cultural and energy. There was an increase of richness of NTFPs with forest succession; however the proportion of NTFPs decreased with age suggesting an increase in non-useful species. This suggests that harvesting from plots of different ages would be the optimal way for local people to get access to a large variety of NTFPs.
- Full Text:
- Date Issued: 2019
- Authors: Njwaxu, Afika
- Date: 2019
- Subjects: Non-timber forest products -- South Africa -- Eastern Cape , Forest ecology -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Non-timber forest products -- South Africa -- Willowvale , Forest ecology -- South Africa -- Willowvale , Rural development -- South Africa -- Willowvale , Forest plants -- South Africa -- Eastern Cape
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/94090 , vital:30999
- Description: The number of people in the Eastern Cape, South Africa, that are engaging in arable cropping has declined markedly over the last few decades. This is due to a number of factors such as a decrease in human capital because of migration of able-bodied people to urban areas, disinclination to participate in farming, raiding of crops by livestock and lack of equipment. This has resulted in abandoned croplands being invaded by trees and shrubs as the start of forest succession leading to a change in species composition and the ecosystem benefits reaped from these sites. Key amongst these benefits is a variety of non-timber forests products (NTFPs) which are an integral part of livelihoods in the area. The study was conducted in Willowvale, on the Wild Coast, South Africa. Aerial photographs were used to determine when cessation of cropping occurred in local fields and when revegetation began in order to determine the age of old fields. Botanical inventory and Braun-Blanquet scale were used to assess species richness, composition and abundance of vegetation in fields abandoned at different times. Focus groups were used to identify NTFPs found in these old fields, their uses as well as rank their importance to the local people. Results showed an increase in woody cover with time since field abandonment. Species richness also increased with age of the old field with approximately three species gained per decade. When species richness was disaggregated by growth forms, herbaceous plants were abundant in the early stages of succession, shrubs in the mature stages and trees increased steadily with time. A total of 177 species were recorded from 50 plots that were sampled during the ecological data collection. Of these, 70 species (39.6%) were identified by the focus group participants as NTFPs. The participants grouped the NTFPs into six categories namely: food, building, medicinal, craft, cultural and energy. There was an increase of richness of NTFPs with forest succession; however the proportion of NTFPs decreased with age suggesting an increase in non-useful species. This suggests that harvesting from plots of different ages would be the optimal way for local people to get access to a large variety of NTFPs.
- Full Text:
- Date Issued: 2019
Assessing the difficulties in teaching and learning of geometry in grade 9 based on the van hiele theory in Komga, East London Education District in South Africa’s Eastern Cape Province
- Authors: Xakwe, Nomawethu
- Date: 2019
- Subjects: Special education Geometry
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10353/16588 , vital:40734
- Description: Geometry prepares learners by equipping them with the knowledge to use higher order thinking skills. The purpose of this research was to assess the difficulties in the teaching and learning of geometry in Grade 9 based on the van Hiele theory in a rural education district in South Africa’s Eastern Cape Province. van Hiele levels complement each other and therefore, geometry educators need to have good pedagogical content knowledge and apply effective teaching and learning strategies to promote geometry learning. The study adopted the pragmatic paradigm and mixed method approach. Convenient sampling based on proximity to the researcher’s workplace was used to select three schools in Komga education circuit for data collection. The educators’ sample consisted of the Grade 9 mathematics educators from each of the three schools making up a total of 3 educators. The learners’ sample consisted of 27 Grade 9 learners,9 from each of the same three schools from where the educators were selected. Quantitative data were collected from educators and learners using different questionnaires. Qualitative data were collected using different in-depth interview schedules for educators and learners. All members of the sample were interviewed. Observations also were carried out in the classroom during teaching and learning of geometry in order to probe the use of strategies by educators. The quantitative data were subjected to descriptive statistical analysis and tabulated. The qualitative data from interviews were thematically analysed and observation data were transcribed, analysed and tabulated. Final conclusions were drawn through triangulating the different data sets. Findings revealed the strengths and weakenesses of the strategies used by educators and the difficulties faced by the learners. Some of the prominent strengths for educators’ strategies were: ability to promote interactive learning and facilitating a conducive environment, enhancement of critical thinking and development of learners’ confidence through participation. Some of the prominent weakenesses of educators’ strategies were:lack of understanding on how to deal with slow learners and inability to change teaching methods to accommodate all learners, thus inhibiting inclusive education.The prominent strenghts for learners were eagerness to participate in all activities and exhibition of confidence in problem solving. The prominent weakenesses of learners were that the respondents struggled with the P a g e | ii geometrical vocabulary and language needed to express their understanding, deficiency in the understanding of geometric concepts and not having the required understanding of the characteristics of triangles. The study recommends that the geometry educators should plan activities for geometry lessons that will encourage the development of geometric vocabulary among their learners. Geometry educators also need to to include questions in their assessments that test conceptual understanding. In-service workshops should be conducted to equip the educators about how to deal with inclusive education.
- Full Text:
- Date Issued: 2019
- Authors: Xakwe, Nomawethu
- Date: 2019
- Subjects: Special education Geometry
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10353/16588 , vital:40734
- Description: Geometry prepares learners by equipping them with the knowledge to use higher order thinking skills. The purpose of this research was to assess the difficulties in the teaching and learning of geometry in Grade 9 based on the van Hiele theory in a rural education district in South Africa’s Eastern Cape Province. van Hiele levels complement each other and therefore, geometry educators need to have good pedagogical content knowledge and apply effective teaching and learning strategies to promote geometry learning. The study adopted the pragmatic paradigm and mixed method approach. Convenient sampling based on proximity to the researcher’s workplace was used to select three schools in Komga education circuit for data collection. The educators’ sample consisted of the Grade 9 mathematics educators from each of the three schools making up a total of 3 educators. The learners’ sample consisted of 27 Grade 9 learners,9 from each of the same three schools from where the educators were selected. Quantitative data were collected from educators and learners using different questionnaires. Qualitative data were collected using different in-depth interview schedules for educators and learners. All members of the sample were interviewed. Observations also were carried out in the classroom during teaching and learning of geometry in order to probe the use of strategies by educators. The quantitative data were subjected to descriptive statistical analysis and tabulated. The qualitative data from interviews were thematically analysed and observation data were transcribed, analysed and tabulated. Final conclusions were drawn through triangulating the different data sets. Findings revealed the strengths and weakenesses of the strategies used by educators and the difficulties faced by the learners. Some of the prominent strengths for educators’ strategies were: ability to promote interactive learning and facilitating a conducive environment, enhancement of critical thinking and development of learners’ confidence through participation. Some of the prominent weakenesses of educators’ strategies were:lack of understanding on how to deal with slow learners and inability to change teaching methods to accommodate all learners, thus inhibiting inclusive education.The prominent strenghts for learners were eagerness to participate in all activities and exhibition of confidence in problem solving. The prominent weakenesses of learners were that the respondents struggled with the P a g e | ii geometrical vocabulary and language needed to express their understanding, deficiency in the understanding of geometric concepts and not having the required understanding of the characteristics of triangles. The study recommends that the geometry educators should plan activities for geometry lessons that will encourage the development of geometric vocabulary among their learners. Geometry educators also need to to include questions in their assessments that test conceptual understanding. In-service workshops should be conducted to equip the educators about how to deal with inclusive education.
- Full Text:
- Date Issued: 2019
Assessing the effects of misplacement of qualified personnel on the implementation of policies: Eastern Cape Department of Basic Education – a case of Head Office, Zone 6- Zwelitsha
- Authors: Ntuni, Zingisa
- Date: 2019
- Subjects: Career development -- South Africa -- Eastern Cape Educational change -- Government policy -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/12513 , vital:39270
- Description: This dissertation sought to review literature on the skills underutilisation in the Eastern Cape Department of Education, a case of Head Office –Zone 6-Zwelitsha. The study intended to delve deeper into the depth of this challenge and understand the effects of this misdeed on the policy implementation in the department. This problem was compounded by the lackadaisical approach to the skills development by the department as it seemed to be employing a shotgun approach to the training and education of its labour-force. The consulted literature pointed to the existence and commonness of the skills underutilisation and its occasioning in reduced outputs and low worker-morale in the workplace. This study played a crucial role in terms of its contribution to the body of knowledge, being a reference point not only for the department of education, nonetheless, for other departments and organisations as well. The study could help the department to rectify its weaknesses and deal with their current challenges of personnel underutilisation. Policy makers and consultants could use the results of this study to formulate policies for their institutions. Lastly, students could also benefit from this study by using it as a source of reference. The qualitative method and case study as a research design employed in the study, semi-structured interviews used as a data collection method, snowballing sampling procedure used. The employees of the Department of Education used as the respondents in the study. The empirical findings in the study revealed the multiplicity of challenges associated with misplacement of qualified personnel in the department which entailed, inter alia, poor implementation of policies, programs and projects, low staff morale, poor delivery of services to the departmental clientele.
- Full Text:
- Date Issued: 2019
- Authors: Ntuni, Zingisa
- Date: 2019
- Subjects: Career development -- South Africa -- Eastern Cape Educational change -- Government policy -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/12513 , vital:39270
- Description: This dissertation sought to review literature on the skills underutilisation in the Eastern Cape Department of Education, a case of Head Office –Zone 6-Zwelitsha. The study intended to delve deeper into the depth of this challenge and understand the effects of this misdeed on the policy implementation in the department. This problem was compounded by the lackadaisical approach to the skills development by the department as it seemed to be employing a shotgun approach to the training and education of its labour-force. The consulted literature pointed to the existence and commonness of the skills underutilisation and its occasioning in reduced outputs and low worker-morale in the workplace. This study played a crucial role in terms of its contribution to the body of knowledge, being a reference point not only for the department of education, nonetheless, for other departments and organisations as well. The study could help the department to rectify its weaknesses and deal with their current challenges of personnel underutilisation. Policy makers and consultants could use the results of this study to formulate policies for their institutions. Lastly, students could also benefit from this study by using it as a source of reference. The qualitative method and case study as a research design employed in the study, semi-structured interviews used as a data collection method, snowballing sampling procedure used. The employees of the Department of Education used as the respondents in the study. The empirical findings in the study revealed the multiplicity of challenges associated with misplacement of qualified personnel in the department which entailed, inter alia, poor implementation of policies, programs and projects, low staff morale, poor delivery of services to the departmental clientele.
- Full Text:
- Date Issued: 2019