Evaluating the efficacy of Hypogeococcus sp. as a biological control agent of the cactaceous weed Cereus jamacaru in South Africa
- Sutton, Guy F, Klein, Hildegard, Paterson, Iain D
- Authors: Sutton, Guy F , Klein, Hildegard , Paterson, Iain D
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/423350 , vital:72051 , xlink:href="https://doi.org/10.1007/s10526-018-9887-3"
- Description: We evaluated the efficacy of Hypogeococcus sp. (Hemiptera: Pseudococcidae) as a biological control agent of the cactaceous weed Cereus jamacaru De Candolle (Queen of the Night cactus) in South Africa. This weed has been described as being under complete biological control due to the action of Hypogeococcus sp., although no formal post-release evaluation had been conducted prior to this study. Biological control was associated with significant reductions in fruiting, plant survival and plant densities, while plant population age structures were negatively affected. Weed populations infected by Hypogeococcus sp. were typified by low or non-existent recruitment and are expected to diminish with time. Populations where Hypogeococcus sp. was absent displayed extensive recruitment, and are predicted to expand or self-replace, if left unchecked. These data indicate that Hypogeococcus sp. has a significant negative effect on C. jamacaru at the individual plant and population level, and given sufficient time provides complete biological control over this weed in South Africa.
- Full Text:
- Date Issued: 2018
- Authors: Sutton, Guy F , Klein, Hildegard , Paterson, Iain D
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/423350 , vital:72051 , xlink:href="https://doi.org/10.1007/s10526-018-9887-3"
- Description: We evaluated the efficacy of Hypogeococcus sp. (Hemiptera: Pseudococcidae) as a biological control agent of the cactaceous weed Cereus jamacaru De Candolle (Queen of the Night cactus) in South Africa. This weed has been described as being under complete biological control due to the action of Hypogeococcus sp., although no formal post-release evaluation had been conducted prior to this study. Biological control was associated with significant reductions in fruiting, plant survival and plant densities, while plant population age structures were negatively affected. Weed populations infected by Hypogeococcus sp. were typified by low or non-existent recruitment and are expected to diminish with time. Populations where Hypogeococcus sp. was absent displayed extensive recruitment, and are predicted to expand or self-replace, if left unchecked. These data indicate that Hypogeococcus sp. has a significant negative effect on C. jamacaru at the individual plant and population level, and given sufficient time provides complete biological control over this weed in South Africa.
- Full Text:
- Date Issued: 2018
Unravelling the unfolding mechanism of human integrin linked kinase by GdmCl-induced denaturation
- Syed, Sunayana B, Khan, Faez I, Khan, Sabab H, Srivastava, Saurabha, Hasan, Gulam M, Lobb, Kevin A, Islam, Asimul, Hassan, M Imtaiyaz, Ahmad, Faizan
- Authors: Syed, Sunayana B , Khan, Faez I , Khan, Sabab H , Srivastava, Saurabha , Hasan, Gulam M , Lobb, Kevin A , Islam, Asimul , Hassan, M Imtaiyaz , Ahmad, Faizan
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447220 , vital:74593 , xlink:href="https://doi.org/10.1016/j.ijbiomac.2018.06.025"
- Description: Integrin-linked kinase (ILK) is a ubiquitously expressed Ser/Thr kinase which plays significant role in the cell-matrix interactions and growth factor signalling. In this study, guanidinium chloride (GdmCl)-induced unfolding of kinase domain of ILK (ILK193–446) was carried out at pH 7.5 and 25 °C. Eventually, denaturation curves of mean residue ellipticity at 222 nm ([θ]222) and fluorescence emission spectrum were analysed to estimate stability parameters. The optical properties maximum emission (λmax) and difference absorption coefficient at 292 nm (Δε292) were analysed. The denaturation curve was measured only in the GdmCl molar concentration ranging 3.0–4.2 M because protein was aggregating below 3.0 M of GdmCl concentrations. The denaturation process of ILK193–446 was found as reversible at [GdmCl] ≥ 3.0 M. Moreover, a coincidence of normalized denaturation curves of optical properties ([θ]222, Δε292 and λmax) suggesting that GdmCl-induced denaturation of ILK193–446 is a two-state process. In addition, 100 ns molecular dynamics simulations were performed to see the effects of GdmCl on the structure and stability of ILK193–446. Both the spectroscopic and molecular dynamics ap proaches provided clear insights into the stability and conformational properties of ILK.
- Full Text:
- Date Issued: 2018
- Authors: Syed, Sunayana B , Khan, Faez I , Khan, Sabab H , Srivastava, Saurabha , Hasan, Gulam M , Lobb, Kevin A , Islam, Asimul , Hassan, M Imtaiyaz , Ahmad, Faizan
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447220 , vital:74593 , xlink:href="https://doi.org/10.1016/j.ijbiomac.2018.06.025"
- Description: Integrin-linked kinase (ILK) is a ubiquitously expressed Ser/Thr kinase which plays significant role in the cell-matrix interactions and growth factor signalling. In this study, guanidinium chloride (GdmCl)-induced unfolding of kinase domain of ILK (ILK193–446) was carried out at pH 7.5 and 25 °C. Eventually, denaturation curves of mean residue ellipticity at 222 nm ([θ]222) and fluorescence emission spectrum were analysed to estimate stability parameters. The optical properties maximum emission (λmax) and difference absorption coefficient at 292 nm (Δε292) were analysed. The denaturation curve was measured only in the GdmCl molar concentration ranging 3.0–4.2 M because protein was aggregating below 3.0 M of GdmCl concentrations. The denaturation process of ILK193–446 was found as reversible at [GdmCl] ≥ 3.0 M. Moreover, a coincidence of normalized denaturation curves of optical properties ([θ]222, Δε292 and λmax) suggesting that GdmCl-induced denaturation of ILK193–446 is a two-state process. In addition, 100 ns molecular dynamics simulations were performed to see the effects of GdmCl on the structure and stability of ILK193–446. Both the spectroscopic and molecular dynamics ap proaches provided clear insights into the stability and conformational properties of ILK.
- Full Text:
- Date Issued: 2018
Characterization and computational studies of a co-crystal of 2-aminobenzimidazole and 2-[(benzoylcarbamothioyl) amino] propanoic acid
- Odame, Felix, Hosten, Eric C, Betz, Richard, Lobb, Kevin A, Tshentu, Zenixole R
- Authors: Odame, Felix , Hosten, Eric C , Betz, Richard , Lobb, Kevin A , Tshentu, Zenixole R
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447030 , vital:74578 , xlink:href="https://doi.org/10.1134/S0022476618050268"
- Description: A novel co-crystal of 2-aminobenzimidazole and 2-[(benzoylcarbamothioyl)amino] propanoic acid is synthesized and characterized by spectroscopy, elemental analysis, GC-MS, and single crystal XRD. A computation of the structures involved in the formation of the co-crystal are carried out and their contribution to reactivity is explained.
- Full Text:
- Date Issued: 2018
- Authors: Odame, Felix , Hosten, Eric C , Betz, Richard , Lobb, Kevin A , Tshentu, Zenixole R
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447030 , vital:74578 , xlink:href="https://doi.org/10.1134/S0022476618050268"
- Description: A novel co-crystal of 2-aminobenzimidazole and 2-[(benzoylcarbamothioyl)amino] propanoic acid is synthesized and characterized by spectroscopy, elemental analysis, GC-MS, and single crystal XRD. A computation of the structures involved in the formation of the co-crystal are carried out and their contribution to reactivity is explained.
- Full Text:
- Date Issued: 2018
Exploring molecular insights into the interaction mechanism of cholesterol derivatives with the Mce4A: A combined spectroscopic and molecular dynamic simulation studies
- Khan, Shagufta, Khan, Faez I, Khan, Parvez, Hasan, Gulam M, Lobb, Kevin A, Islam, Asimul, Ahmad, Faizan, Hassan, M Imtaiyaz
- Authors: Khan, Shagufta , Khan, Faez I , Khan, Parvez , Hasan, Gulam M , Lobb, Kevin A , Islam, Asimul , Ahmad, Faizan , Hassan, M Imtaiyaz
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447041 , vital:74579 , xlink:href="https://doi.org/10.1016/j.ijbiomac.2017.12.160"
- Description: Mammalian cell entry protein (Mce4A) is a member of MCE-family, and is being considered as a potential drug target of Mycobacterium tuberculosis infection because it is required for invasion and latent survival of pathogen by utilizing host's cholesterol. In the present study, we performed molecular docking followed by 100 ns MD simulation studies to understand the mechanism of interaction of Mce4A to the cholesterol derivatives and probucol. The selected ligands, cholesterol, 25-hydroxycholesterol, 5-cholesten-3β-ol-7-one and probucol bind to the predicted active site cavity of Mce4A, and complexes remain stable during entire simulation of 100 ns. In silico studies were further validated by fluorescence-binding studies to calculate actual binding affinity and number of binding site(s). The non-toxicity of all ligands was confirmed on human monocytic cell (THP1) by MTT assay. This work provides a deeper insight into the mechanism of interaction of Mce4A to cholesterol derivatives, which may be further exploited to design potential and specific inhibitors to ameliorate the Mycobacterium pathogenesis.
- Full Text:
- Date Issued: 2018
- Authors: Khan, Shagufta , Khan, Faez I , Khan, Parvez , Hasan, Gulam M , Lobb, Kevin A , Islam, Asimul , Ahmad, Faizan , Hassan, M Imtaiyaz
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447041 , vital:74579 , xlink:href="https://doi.org/10.1016/j.ijbiomac.2017.12.160"
- Description: Mammalian cell entry protein (Mce4A) is a member of MCE-family, and is being considered as a potential drug target of Mycobacterium tuberculosis infection because it is required for invasion and latent survival of pathogen by utilizing host's cholesterol. In the present study, we performed molecular docking followed by 100 ns MD simulation studies to understand the mechanism of interaction of Mce4A to the cholesterol derivatives and probucol. The selected ligands, cholesterol, 25-hydroxycholesterol, 5-cholesten-3β-ol-7-one and probucol bind to the predicted active site cavity of Mce4A, and complexes remain stable during entire simulation of 100 ns. In silico studies were further validated by fluorescence-binding studies to calculate actual binding affinity and number of binding site(s). The non-toxicity of all ligands was confirmed on human monocytic cell (THP1) by MTT assay. This work provides a deeper insight into the mechanism of interaction of Mce4A to cholesterol derivatives, which may be further exploited to design potential and specific inhibitors to ameliorate the Mycobacterium pathogenesis.
- Full Text:
- Date Issued: 2018
Seed extract of Psoralea corylifolia and its constituent bakuchiol impairs AHL-based quorum sensing and biofilm formation in food-and human-related pathogens
- Husain, Fohad M, Ahmad, Iqbal, Khan, Faez I, Al-Shabib, Nasser A, Baig, Mohammad H, Hussain, Afzal, Rehman, Md T, Alajmi, Mohamed F, Lobb, Kevin A
- Authors: Husain, Fohad M , Ahmad, Iqbal , Khan, Faez I , Al-Shabib, Nasser A , Baig, Mohammad H , Hussain, Afzal , Rehman, Md T , Alajmi, Mohamed F , Lobb, Kevin A
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447182 , vital:74590 , xlink:href="https://doi.org/10.3389/fcimb.2018.00351"
- Description: The emergence of multi-drug resistance in pathogenic bacteria in clinical settings as well as food-borne infections has become a serious health concern. The problem of drug resistance necessitates the need for alternative novel therapeutic strategies to combat this menace. One such approach is targeting the quorum-sensing (QS) controlled virulence and biofilm formation. In this study, we first screened different fractions of Psoralea corylifolia (seed) for their anti-QS property in the Chromobacterium violaceum 12472 strain.
- Full Text:
- Date Issued: 2018
- Authors: Husain, Fohad M , Ahmad, Iqbal , Khan, Faez I , Al-Shabib, Nasser A , Baig, Mohammad H , Hussain, Afzal , Rehman, Md T , Alajmi, Mohamed F , Lobb, Kevin A
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447182 , vital:74590 , xlink:href="https://doi.org/10.3389/fcimb.2018.00351"
- Description: The emergence of multi-drug resistance in pathogenic bacteria in clinical settings as well as food-borne infections has become a serious health concern. The problem of drug resistance necessitates the need for alternative novel therapeutic strategies to combat this menace. One such approach is targeting the quorum-sensing (QS) controlled virulence and biofilm formation. In this study, we first screened different fractions of Psoralea corylifolia (seed) for their anti-QS property in the Chromobacterium violaceum 12472 strain.
- Full Text:
- Date Issued: 2018
Synthesis, characterization and DPPH scavenging activity of some benzimidazole derivatives
- Odame, Felix, Krause, Jason, Hosten, Eric C, Betz, Richard, Lobb, Kevin A, Tshentu, Zenixole R, Frost, Carminita L
- Authors: Odame, Felix , Krause, Jason , Hosten, Eric C , Betz, Richard , Lobb, Kevin A , Tshentu, Zenixole R , Frost, Carminita L
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447209 , vital:74592 , xlink:href="https://dx.doi.org/10.4314/bcse.v32i2.8 "
- Description: A base-catalyzed conversion of aldehydes to benzimidazoles has been achieved. The compounds have been characterized by IR, NMR, micoranalysis, and GC-MS. The reaction for the formation of benzimidazoles has been monitored with 1 H NMR and IR. The crystal structures of two derivatives, 2-(2- chlorophenyl)-1H-benzimidazole and 2-(1H-benzimidazol-2-yl)-4-nitrophenol, are presented. A study of the DPPH scavenging activity of these compounds showed that 2-(1H-benzimidazol-2-yl)phenol (2), 2-p-tolyl-1Hbenzimidazole (3) and 2-(4-methoxyphenyl)-1H-benzimidazole (7) gave IC50 values 1974, 773 and 800 µM.
- Full Text:
- Date Issued: 2018
- Authors: Odame, Felix , Krause, Jason , Hosten, Eric C , Betz, Richard , Lobb, Kevin A , Tshentu, Zenixole R , Frost, Carminita L
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447209 , vital:74592 , xlink:href="https://dx.doi.org/10.4314/bcse.v32i2.8 "
- Description: A base-catalyzed conversion of aldehydes to benzimidazoles has been achieved. The compounds have been characterized by IR, NMR, micoranalysis, and GC-MS. The reaction for the formation of benzimidazoles has been monitored with 1 H NMR and IR. The crystal structures of two derivatives, 2-(2- chlorophenyl)-1H-benzimidazole and 2-(1H-benzimidazol-2-yl)-4-nitrophenol, are presented. A study of the DPPH scavenging activity of these compounds showed that 2-(1H-benzimidazol-2-yl)phenol (2), 2-p-tolyl-1Hbenzimidazole (3) and 2-(4-methoxyphenyl)-1H-benzimidazole (7) gave IC50 values 1974, 773 and 800 µM.
- Full Text:
- Date Issued: 2018
Prospects for biological control of cactus weeds in Namibia
- Paterson, Iain D, Manheimmer, C A, Zimmermann, Helmuth G
- Authors: Paterson, Iain D , Manheimmer, C A , Zimmermann, Helmuth G
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/417522 , vital:71460 , xlink:href="https://doi.org/10.1080/09583157.2018.1562040"
- Description: Australia and South Africa have a long history of sharing successful biocontrol agents for cactus weeds but other countries, such as Namibia, could also benefit. There are four biological control agents that are widely utilised in South Africa and/or Australia for the control of 10 invasive alien Cactaceae in Namibia.
- Full Text:
- Date Issued: 2018
- Authors: Paterson, Iain D , Manheimmer, C A , Zimmermann, Helmuth G
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/417522 , vital:71460 , xlink:href="https://doi.org/10.1080/09583157.2018.1562040"
- Description: Australia and South Africa have a long history of sharing successful biocontrol agents for cactus weeds but other countries, such as Namibia, could also benefit. There are four biological control agents that are widely utilised in South Africa and/or Australia for the control of 10 invasive alien Cactaceae in Namibia.
- Full Text:
- Date Issued: 2018
Synergizing technology and health promotion for the prevention of tuberculosis
- Srinivas, Sunitha C, Mtolo, L T, Duxbury, Theodore O, Bradshaw, Karen L
- Authors: Srinivas, Sunitha C , Mtolo, L T , Duxbury, Theodore O , Bradshaw, Karen L
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/460629 , vital:75971
- Description: With the rapid global increase in the prevalence of tuberculosis, health promotion is crucial to raise communal health awareness. This service-learning health promotion activity aimed to increase awareness of TB amongst school learners in attendance at the 2016 National Science Festival. A computer-based pre- and post-intervention quiz, an educational poster, an interactive word search game, and a take-home information leaflet were utilized in a health promotion exhibit. Junior and senior school learners who participated in the exhibit showed significant improvements in their post-educational intervention scores. The exhibit was effective as a preliminary measure in reinforcing health information and raising awareness.
- Full Text:
- Date Issued: 2018
- Authors: Srinivas, Sunitha C , Mtolo, L T , Duxbury, Theodore O , Bradshaw, Karen L
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/460629 , vital:75971
- Description: With the rapid global increase in the prevalence of tuberculosis, health promotion is crucial to raise communal health awareness. This service-learning health promotion activity aimed to increase awareness of TB amongst school learners in attendance at the 2016 National Science Festival. A computer-based pre- and post-intervention quiz, an educational poster, an interactive word search game, and a take-home information leaflet were utilized in a health promotion exhibit. Junior and senior school learners who participated in the exhibit showed significant improvements in their post-educational intervention scores. The exhibit was effective as a preliminary measure in reinforcing health information and raising awareness.
- Full Text:
- Date Issued: 2018
Health education on diabetes at a South African national science festival
- Bradshaw, Karen L, Mhlongo, M, Srinivas, Sunitha C, Marara P
- Authors: Bradshaw, Karen L , Mhlongo, M , Srinivas, Sunitha C , Marara P
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/460074 , vital:75890
- Description: Diabetes is one of the non-communicable diseases with a major negative impact on the health and development of South Africans. Empowering the population’s understanding of the condition, with health-literacy appropriate approaches, is one of the interventions that allows discussions around the prevention of diabetes. Objective. To determine the effects of a health education programme on increasing knowledge about diabetes and encouraging preventive measures. Method. A public health education exhibition was held by a pharmacy student at a national science festival. It incorporated presentations, posters, health models, word-search games, information leaflets and a computer-based quiz consisting of pre- and post-intervention questions. Results. Junior and senior school learners participated in the computer-based quiz. Results from the junior school pre-intervention phase showed that learners had a fair prior knowledge of diabetes, with an overall score of 52.8%. Improvement in their overall mean score at the 5% significance level was noted (p=0.020). There was a significant difference in the mean score after the intervention at the 1% level (government schools: 65.5 (standard error (SE) 3.1)%, independent schools: 45.9 (6.2)%; p=0.006). Of the senior learners 53.7% (n=137) indicated that they use computers at school, while 118 (46.3%) did not have access to computers. The improvement in overall knowledge of the senior participants after the intervention was significant at the 0.1% level (p is less than 0.001). Conclusion. The health education offered by the pharmacy student's project was interactive and used an interdisciplinary approach to improve health literacy and raise awareness of diabetes. This is a tested intervention that may be adopted for improving health literacy among schoolchildren.
- Full Text:
- Date Issued: 2018
- Authors: Bradshaw, Karen L , Mhlongo, M , Srinivas, Sunitha C , Marara P
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/460074 , vital:75890
- Description: Diabetes is one of the non-communicable diseases with a major negative impact on the health and development of South Africans. Empowering the population’s understanding of the condition, with health-literacy appropriate approaches, is one of the interventions that allows discussions around the prevention of diabetes. Objective. To determine the effects of a health education programme on increasing knowledge about diabetes and encouraging preventive measures. Method. A public health education exhibition was held by a pharmacy student at a national science festival. It incorporated presentations, posters, health models, word-search games, information leaflets and a computer-based quiz consisting of pre- and post-intervention questions. Results. Junior and senior school learners participated in the computer-based quiz. Results from the junior school pre-intervention phase showed that learners had a fair prior knowledge of diabetes, with an overall score of 52.8%. Improvement in their overall mean score at the 5% significance level was noted (p=0.020). There was a significant difference in the mean score after the intervention at the 1% level (government schools: 65.5 (standard error (SE) 3.1)%, independent schools: 45.9 (6.2)%; p=0.006). Of the senior learners 53.7% (n=137) indicated that they use computers at school, while 118 (46.3%) did not have access to computers. The improvement in overall knowledge of the senior participants after the intervention was significant at the 0.1% level (p is less than 0.001). Conclusion. The health education offered by the pharmacy student's project was interactive and used an interdisciplinary approach to improve health literacy and raise awareness of diabetes. This is a tested intervention that may be adopted for improving health literacy among schoolchildren.
- Full Text:
- Date Issued: 2018
The relative importance of autochthony along the longitudinal gradient of a small South African river influenced by agricultural activities
- Moyo, Sydney, Richoux, Nicole B
- Authors: Moyo, Sydney , Richoux, Nicole B
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/454392 , vital:75340 , xlink:href="https://doi.org/10.1016/j.fooweb.2018.e00082"
- Description: Generalisations about the sources of organic matter that support aquatic consumers are usually focussed on certain parts of the world (particularly the northern hemisphere) and large rivers, and therefore may not include the full spectrum of food webs that occur in the southern hemisphere (particularly those with high nitrogen inputs). We studied the relative importance of organic matter sources to macroinvertebrate consumers in a small South African river. Based on previous observations of our system of interest and other agricultural streams, we hypothesised that (a) the carbon fuelling consumers is primarily derived from autochthonous (in situ) food sources regardless of sampling time and, (b) the contribution of autochthonous basal resources to consumers increases in importance as the river widens (from upper to downstream reaches). To test these predictions, stable carbon (δ13C) and nitrogen (δ15N) isotopes were used to estimate the contributions of local algal and land-based production to aquatic macroinvertebrates over space (six sites) and time (four sampling occasions between November 2012 and September 2013) along the Kowie River, South Africa. Mixing models revealed that consumers in the upper reaches assimilated terrestrially-derived allochthonous organic matter, and consumers in the middle and lower reaches assimilated primarily autochthonous basal resources (macrophytes and algae). The isotopic values of consumers and their food sources changed over time, indicating that food sources and consumers should be analysed many times throughout the year to capture that variability and ensure that ephemeral components of the food web are not missed. Our results enhance the growing body of literature on the dynamics of riverine systems and indicate the importance of autochthony in a small temperate river with high nitrogen inputs.
- Full Text:
- Date Issued: 2018
- Authors: Moyo, Sydney , Richoux, Nicole B
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/454392 , vital:75340 , xlink:href="https://doi.org/10.1016/j.fooweb.2018.e00082"
- Description: Generalisations about the sources of organic matter that support aquatic consumers are usually focussed on certain parts of the world (particularly the northern hemisphere) and large rivers, and therefore may not include the full spectrum of food webs that occur in the southern hemisphere (particularly those with high nitrogen inputs). We studied the relative importance of organic matter sources to macroinvertebrate consumers in a small South African river. Based on previous observations of our system of interest and other agricultural streams, we hypothesised that (a) the carbon fuelling consumers is primarily derived from autochthonous (in situ) food sources regardless of sampling time and, (b) the contribution of autochthonous basal resources to consumers increases in importance as the river widens (from upper to downstream reaches). To test these predictions, stable carbon (δ13C) and nitrogen (δ15N) isotopes were used to estimate the contributions of local algal and land-based production to aquatic macroinvertebrates over space (six sites) and time (four sampling occasions between November 2012 and September 2013) along the Kowie River, South Africa. Mixing models revealed that consumers in the upper reaches assimilated terrestrially-derived allochthonous organic matter, and consumers in the middle and lower reaches assimilated primarily autochthonous basal resources (macrophytes and algae). The isotopic values of consumers and their food sources changed over time, indicating that food sources and consumers should be analysed many times throughout the year to capture that variability and ensure that ephemeral components of the food web are not missed. Our results enhance the growing body of literature on the dynamics of riverine systems and indicate the importance of autochthony in a small temperate river with high nitrogen inputs.
- Full Text:
- Date Issued: 2018
Spatial and temporal variability in the nutritional quality of basal resources along a temperate river/estuary continuum
- Richoux, Nicole B, Bergamino, Leandro, Moyo, Sydney, Dalu, Tatenda
- Authors: Richoux, Nicole B , Bergamino, Leandro , Moyo, Sydney , Dalu, Tatenda
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/454375 , vital:75339 , xlink:href="https://doi.org/10.1016/j.orggeochem.2017.11.009"
- Description: The nature and quality of basal resources within aquatic food webs are complex and have the potential to shift over space and time. We used fatty acid analysis to assess variations in the nutritional structure of the suspended and basal pools along an entire river system, and to assess the contributions of vascular plant (i.e., mainly of terrestrial origin, but could include aquatic macrophytes) vs algal (i.e., aquatic origin) sources to the suspended particulate matter (SPM) pools. Samples were collected in a temperate South African river on four occasions between September 2012 and June 2013. We found orderly patterns in the fatty acid composition of the basal resources at the sites during most seasons. Regardless of site or season, the benthic algal pools (epiphyton, epipelon and epilithon) were the most nutritionally rich resources based on essential fatty acid contents and diatom indices. During early and late spring, proportions of essential fatty acids in the epiphyton decreased downstream where increased light was available, consistent with predictions from the light:nutrient hypothesis (but inconsistent with epilithon and epipelon results). There were substantial changes in vascular plant contributions to the SPM pools along the river, but the same patterns were not produced in all seasons. Of all the river models considered, the data were more consistent with the riverine productivity model, which particularly emphasises the importance of autotrophic production in rivers. Our study provides new detail on the complexity of basal resource nutritional quality and how it can shift along a lotic system over time.
- Full Text:
- Date Issued: 2018
- Authors: Richoux, Nicole B , Bergamino, Leandro , Moyo, Sydney , Dalu, Tatenda
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/454375 , vital:75339 , xlink:href="https://doi.org/10.1016/j.orggeochem.2017.11.009"
- Description: The nature and quality of basal resources within aquatic food webs are complex and have the potential to shift over space and time. We used fatty acid analysis to assess variations in the nutritional structure of the suspended and basal pools along an entire river system, and to assess the contributions of vascular plant (i.e., mainly of terrestrial origin, but could include aquatic macrophytes) vs algal (i.e., aquatic origin) sources to the suspended particulate matter (SPM) pools. Samples were collected in a temperate South African river on four occasions between September 2012 and June 2013. We found orderly patterns in the fatty acid composition of the basal resources at the sites during most seasons. Regardless of site or season, the benthic algal pools (epiphyton, epipelon and epilithon) were the most nutritionally rich resources based on essential fatty acid contents and diatom indices. During early and late spring, proportions of essential fatty acids in the epiphyton decreased downstream where increased light was available, consistent with predictions from the light:nutrient hypothesis (but inconsistent with epilithon and epipelon results). There were substantial changes in vascular plant contributions to the SPM pools along the river, but the same patterns were not produced in all seasons. Of all the river models considered, the data were more consistent with the riverine productivity model, which particularly emphasises the importance of autotrophic production in rivers. Our study provides new detail on the complexity of basal resource nutritional quality and how it can shift along a lotic system over time.
- Full Text:
- Date Issued: 2018
Transforming while transferring: An exploratory study of how transferability of skills is key in the transformation of higher education
- Bazana, Sandiso, McLaren, Logan, Kabungaidze, Trust
- Authors: Bazana, Sandiso , McLaren, Logan , Kabungaidze, Trust
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/453793 , vital:75286 , xlink:href="https://hdl.handle.net/10520/EJC-102f9d32bf"
- Description: The importance of skills within the transformation of higher education is a crucial factor that has been insufficiently considered. Transformation in terms of higher education forms a fundamental part of the post-apartheid South African society. This transformation movement seems to exclude the possible role and contributions of the older generation of academics. Using a social constructionist viewpoint, this qualitative study sought to bring to the debate of transformation of higher education the important question of skills transferability between older generation academics and the new generation. From interviewing five retired white academics, the study found that institutional culture and implementation of labour legislation through the Human Resources department by the university in question affect the transferability of skills and that proper programmes of voluntary mentorship should be put in place as to allow the growth of both the older generation and new generation academics. The use of new generation academics’ perspectives could yield more results and findings that can further this area of study, as well as allow a more diverse and richer understanding of the perception of skills transferability within the transformation of higher education institutions. This further understanding for research is needed to emphasise the importance of knowledge production through the integration of both young academics’ as well as older academics’ perspectives. This is to be achieved by engaging with other universities and academics, so that a broader analysis of skills transferability within higher education can be understood.
- Full Text:
- Date Issued: 2018
- Authors: Bazana, Sandiso , McLaren, Logan , Kabungaidze, Trust
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/453793 , vital:75286 , xlink:href="https://hdl.handle.net/10520/EJC-102f9d32bf"
- Description: The importance of skills within the transformation of higher education is a crucial factor that has been insufficiently considered. Transformation in terms of higher education forms a fundamental part of the post-apartheid South African society. This transformation movement seems to exclude the possible role and contributions of the older generation of academics. Using a social constructionist viewpoint, this qualitative study sought to bring to the debate of transformation of higher education the important question of skills transferability between older generation academics and the new generation. From interviewing five retired white academics, the study found that institutional culture and implementation of labour legislation through the Human Resources department by the university in question affect the transferability of skills and that proper programmes of voluntary mentorship should be put in place as to allow the growth of both the older generation and new generation academics. The use of new generation academics’ perspectives could yield more results and findings that can further this area of study, as well as allow a more diverse and richer understanding of the perception of skills transferability within the transformation of higher education institutions. This further understanding for research is needed to emphasise the importance of knowledge production through the integration of both young academics’ as well as older academics’ perspectives. This is to be achieved by engaging with other universities and academics, so that a broader analysis of skills transferability within higher education can be understood.
- Full Text:
- Date Issued: 2018
Could differences in implicit attitudes to sexual concurrency play a role in generalized HIV epidemics?
- Kenyon, Chris R, Wolfs, Kenny, Osbak, Kara, van Hal, Guido, Zondo, Sizwe, van Lankveld, J
- Authors: Kenyon, Chris R , Wolfs, Kenny , Osbak, Kara , van Hal, Guido , Zondo, Sizwe , van Lankveld, J
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/450574 , vital:74962 , xlink:href="10.12688/f1000research.14951.2"
- Description: Despite medical advances in Highly Active Antiretroviral Therapy (HAART), patients living with HIV continue to be at risk for developing HIV-associated neurocognitive disorders (HAND). The optimization of non-HAART interventions, including cognitive rehabilitation therapy (CRT), shows promise in reversing the impact of HAND. No data exist indicating the efficacy of CRT in remediating attention skills following neuroHIV. This paper presents a meta-analysis of randomised and non-randomised controlled trials (RCTs) to remediate attention skills following HIV CRT.
- Full Text:
- Date Issued: 2018
- Authors: Kenyon, Chris R , Wolfs, Kenny , Osbak, Kara , van Hal, Guido , Zondo, Sizwe , van Lankveld, J
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/450574 , vital:74962 , xlink:href="10.12688/f1000research.14951.2"
- Description: Despite medical advances in Highly Active Antiretroviral Therapy (HAART), patients living with HIV continue to be at risk for developing HIV-associated neurocognitive disorders (HAND). The optimization of non-HAART interventions, including cognitive rehabilitation therapy (CRT), shows promise in reversing the impact of HAND. No data exist indicating the efficacy of CRT in remediating attention skills following neuroHIV. This paper presents a meta-analysis of randomised and non-randomised controlled trials (RCTs) to remediate attention skills following HIV CRT.
- Full Text:
- Date Issued: 2018
Yeast-baculovirus synergism: investigating mixed infections for improved management of the false codling moth, Thaumatotibia leucotreta
- Authors: Van der Merwe, Marcél
- Date: 2018
- Subjects: Cryptophlebia leucotreta , Baculoviruses , Yeast , Citrus Diseases and pests , Biological pest control agents , Pests Integrated control
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/62963 , vital:28347
- Description: Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) or otherwise commonly known as the false codling moth is an indigenous pest of the citrus industry in southern Africa. The pest is highly significant as it impacts negatively on the export of fresh citrus fruits from South Africa to international markets. To control T. leucotreta in South Africa, an integrated pest management (IPM) programme has been implemented. One component of this programme is the baculovirus Cryptophlebia leucotreta granulovirus (CrleGV-SA) which has been formulated into the products Cryptogran™ and Cryptex®. It has previously been reported that there is a mutualistic association between Cydia pomonella (L.) (Lepidoptera: Tortricidae) also known as codling moth, and epiphytic yeasts. Cydia pomonella larval feeding galleries were colonised by yeasts and this, in turn, reduced larval mortality and enhanced larval development. It has been demonstrated in laboratory assays and field trials that combining yeast and brown cane sugar with Cydia pomonella granulovirus (CpGV) significantly increased larval mortality and lowered the proportion of injured apple fruit. This suggests that yeasts can enhance the effectiveness of an insect virus in managing pest larvae. In this study, we proposed to determine which species of yeast occur naturally in the digestive tract, frass and on the epidermis of T. leucotreta larvae and to examine whether any of these yeasts, when combined with the CrleGV-SA, have a synergistic effect in increasing mortality of T. leucotreta larvae. Firstly, Navel oranges infested with T. leucotreta larvae were collected from orchards in Sundays River Valley in Eastern Cape of South Africa. Larvae were extracted and analysed for the presence of yeast on their surface, or in their gut and frass. Four yeasts were isolated from T. leucotreta larvae and identified down to species level via PCR amplification and sequencing of internal transcribed spacer (ITS) region and D1/D2 domain of the large subunit (LSU) of rDNA region. These yeasts were isolated from the frass, epidermis and digestive tract of T. leucotreta larvae. The yeast isolates were identified as Meyerozyma caribbica, Pichia kluyveri, Pichia kudriavzevii and Hanseniaspora opuntiae. A yeast preference assay was conducted on female T. leucotreta moths to examine whether any of the isolated yeast species affected their oviposition preference. Navel oranges were inoculated with the isolated yeast species at a concentration of 6 × 108 cells.ml-1. The assay also included a Brewer’s yeast and distilled water control. Pichia kudriavzevii was shown to be the preferred yeast species for oviposition, as significantly more eggs were deposited on Navel oranges inoculated with this yeast compared to the other treatments. Lastly, a detached fruit bioassay was performed to evaluate the efficacy of mixing P. kudriavzevii with CrleGV-SA to enhance T. leucotreta larvae mortality. Pichia kudriavzevii was selected as it was demonstrated as having an effect on the oviposition preference of female T. leucotreta moths. The concentration at which P. kudriavzevii was applied remained the same as in the preference assay while CrleGV-SA was applied at lethal concentration required to kill 50 % of the population (9.31 × 107 OBs.ml-1). Although an increase in larval mortality was observed between CrleGV-SA being applied alone and the yeast/virus mixture, this result was determined not to be statistically significant. The experiments performed in this study provide a platform for further research into the application of a yeast-virus combination as a novel control option for T. leucotreta in the field. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2018
- Full Text:
- Date Issued: 2018
- Authors: Van der Merwe, Marcél
- Date: 2018
- Subjects: Cryptophlebia leucotreta , Baculoviruses , Yeast , Citrus Diseases and pests , Biological pest control agents , Pests Integrated control
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/62963 , vital:28347
- Description: Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) or otherwise commonly known as the false codling moth is an indigenous pest of the citrus industry in southern Africa. The pest is highly significant as it impacts negatively on the export of fresh citrus fruits from South Africa to international markets. To control T. leucotreta in South Africa, an integrated pest management (IPM) programme has been implemented. One component of this programme is the baculovirus Cryptophlebia leucotreta granulovirus (CrleGV-SA) which has been formulated into the products Cryptogran™ and Cryptex®. It has previously been reported that there is a mutualistic association between Cydia pomonella (L.) (Lepidoptera: Tortricidae) also known as codling moth, and epiphytic yeasts. Cydia pomonella larval feeding galleries were colonised by yeasts and this, in turn, reduced larval mortality and enhanced larval development. It has been demonstrated in laboratory assays and field trials that combining yeast and brown cane sugar with Cydia pomonella granulovirus (CpGV) significantly increased larval mortality and lowered the proportion of injured apple fruit. This suggests that yeasts can enhance the effectiveness of an insect virus in managing pest larvae. In this study, we proposed to determine which species of yeast occur naturally in the digestive tract, frass and on the epidermis of T. leucotreta larvae and to examine whether any of these yeasts, when combined with the CrleGV-SA, have a synergistic effect in increasing mortality of T. leucotreta larvae. Firstly, Navel oranges infested with T. leucotreta larvae were collected from orchards in Sundays River Valley in Eastern Cape of South Africa. Larvae were extracted and analysed for the presence of yeast on their surface, or in their gut and frass. Four yeasts were isolated from T. leucotreta larvae and identified down to species level via PCR amplification and sequencing of internal transcribed spacer (ITS) region and D1/D2 domain of the large subunit (LSU) of rDNA region. These yeasts were isolated from the frass, epidermis and digestive tract of T. leucotreta larvae. The yeast isolates were identified as Meyerozyma caribbica, Pichia kluyveri, Pichia kudriavzevii and Hanseniaspora opuntiae. A yeast preference assay was conducted on female T. leucotreta moths to examine whether any of the isolated yeast species affected their oviposition preference. Navel oranges were inoculated with the isolated yeast species at a concentration of 6 × 108 cells.ml-1. The assay also included a Brewer’s yeast and distilled water control. Pichia kudriavzevii was shown to be the preferred yeast species for oviposition, as significantly more eggs were deposited on Navel oranges inoculated with this yeast compared to the other treatments. Lastly, a detached fruit bioassay was performed to evaluate the efficacy of mixing P. kudriavzevii with CrleGV-SA to enhance T. leucotreta larvae mortality. Pichia kudriavzevii was selected as it was demonstrated as having an effect on the oviposition preference of female T. leucotreta moths. The concentration at which P. kudriavzevii was applied remained the same as in the preference assay while CrleGV-SA was applied at lethal concentration required to kill 50 % of the population (9.31 × 107 OBs.ml-1). Although an increase in larval mortality was observed between CrleGV-SA being applied alone and the yeast/virus mixture, this result was determined not to be statistically significant. The experiments performed in this study provide a platform for further research into the application of a yeast-virus combination as a novel control option for T. leucotreta in the field. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2018
- Full Text:
- Date Issued: 2018
Two new species of Acontias (Acontinae, Scincidae) from the Mpumalanga Highveld escarpment of South Africa
- Conradie, Werner C, Busschau, Theo, Edwards, Shelley
- Authors: Conradie, Werner C , Busschau, Theo , Edwards, Shelley
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/462735 , vital:76330 , xlink:href="https://europepmc.org/article/med/30313280"
- Description: The African genus of fossorial legless lizards (Acontias Cuvier) currently comprises 26 species and subspecies. In a recent study on the two disjunct populations of Acontias breviceps Essex, the presence of cryptic species was discovered. Here, we increase the sampling size and describe these disjunct populations from the Mpumalanga Escarpment of South Africa as new species. The new species differ from congeners based on a combination of factors, including the number of midbody, ventral, and subcaudal scale counts, ventral pigmentation, allopatric distributions, and genetic divergences. The new species are genetically distant from nominal A. breviceps, with which it shares overall pigmentation and scalation. The new description adds to the growing number of Mpumalanga escarpment endemic reptiles, and highlights the area as a biodiversity hotspot. The use of vertebral counts as a distinguishing character between species is briefly discussed.
- Full Text:
- Date Issued: 2018
- Authors: Conradie, Werner C , Busschau, Theo , Edwards, Shelley
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/462735 , vital:76330 , xlink:href="https://europepmc.org/article/med/30313280"
- Description: The African genus of fossorial legless lizards (Acontias Cuvier) currently comprises 26 species and subspecies. In a recent study on the two disjunct populations of Acontias breviceps Essex, the presence of cryptic species was discovered. Here, we increase the sampling size and describe these disjunct populations from the Mpumalanga Escarpment of South Africa as new species. The new species differ from congeners based on a combination of factors, including the number of midbody, ventral, and subcaudal scale counts, ventral pigmentation, allopatric distributions, and genetic divergences. The new species are genetically distant from nominal A. breviceps, with which it shares overall pigmentation and scalation. The new description adds to the growing number of Mpumalanga escarpment endemic reptiles, and highlights the area as a biodiversity hotspot. The use of vertebral counts as a distinguishing character between species is briefly discussed.
- Full Text:
- Date Issued: 2018
Efficient Biometric Access Control for Larger Scale Populations
- Brown, Dane L, Bradshaw, Karen L
- Authors: Brown, Dane L , Bradshaw, Karen L
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/465667 , vital:76630 , xlink:href="https://www.researchgate.net/profile/Dane-Brown-2/publication/335378829_Efficient_Biometric_Access_Control_for_Larger_Scale_Populations/links/5d61159ea6fdccc32ccd2c8a/Efficient-Biometric-Access-Control-for-Larger-Scale-Populations.pdf"
- Description: Biometric applications and databases are growing at an alarming rate. Processing large or complex biometric data induces longer wait times that can limit usability during application. This paper focuses on increasing the processing speed of biometric data, and calls for a parallel approach to data processing that is beyond the capability of a central processing unit (CPU). The graphical processing unit (GPU) is effectively utilized with compute unified device architecture (CUDA), and results in at least triple the processing speed when compared with a previously presented accurate and secure multimodal biometric system. When saturating the CPU-only implementation with more individuals than the available thread count, the GPU-assisted implementation outperforms it exponentially. The GPU-assisted implementation is also validated to have the same accuracy of the original system, and thus shows promising advancements in both accuracy and processing speed in the challenging big data world.
- Full Text:
- Date Issued: 2018
- Authors: Brown, Dane L , Bradshaw, Karen L
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/465667 , vital:76630 , xlink:href="https://www.researchgate.net/profile/Dane-Brown-2/publication/335378829_Efficient_Biometric_Access_Control_for_Larger_Scale_Populations/links/5d61159ea6fdccc32ccd2c8a/Efficient-Biometric-Access-Control-for-Larger-Scale-Populations.pdf"
- Description: Biometric applications and databases are growing at an alarming rate. Processing large or complex biometric data induces longer wait times that can limit usability during application. This paper focuses on increasing the processing speed of biometric data, and calls for a parallel approach to data processing that is beyond the capability of a central processing unit (CPU). The graphical processing unit (GPU) is effectively utilized with compute unified device architecture (CUDA), and results in at least triple the processing speed when compared with a previously presented accurate and secure multimodal biometric system. When saturating the CPU-only implementation with more individuals than the available thread count, the GPU-assisted implementation outperforms it exponentially. The GPU-assisted implementation is also validated to have the same accuracy of the original system, and thus shows promising advancements in both accuracy and processing speed in the challenging big data world.
- Full Text:
- Date Issued: 2018
Core-modified rubyrins with phenanthrene-fused pyrrole rings
- Yuan, Xuemei, Li, Minzhi, Meng, Ting, Mack, John, Soy, Rodah C, Nyokong, Tebello, Zhu, Weihua, Xu, Haijun, Liang, Xu
- Authors: Yuan, Xuemei , Li, Minzhi , Meng, Ting , Mack, John , Soy, Rodah C , Nyokong, Tebello , Zhu, Weihua , Xu, Haijun , Liang, Xu
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/234568 , vital:50209 , xlink:href="https://doi.org/10.1016/j.dyepig.2018.05.045"
- Description: Three fused-ring-expanded rubyrins with modified macrocyclic core have been synthesized and characterized. A series of spectroscopic, electrochemical measurements and a set of theoretical calculations demonstrate that the core-modification of the inner core of rubyrins has a large influence on the electronic structure. Colorimetric changes are observe that demonstrate that these core-modified rubyrins could be used as selective Hg2+ ion sensors. These properties can be fine-tuned by introducing lipophilic substituents on the meso-aryl rings.
- Full Text:
- Date Issued: 2018
- Authors: Yuan, Xuemei , Li, Minzhi , Meng, Ting , Mack, John , Soy, Rodah C , Nyokong, Tebello , Zhu, Weihua , Xu, Haijun , Liang, Xu
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/234568 , vital:50209 , xlink:href="https://doi.org/10.1016/j.dyepig.2018.05.045"
- Description: Three fused-ring-expanded rubyrins with modified macrocyclic core have been synthesized and characterized. A series of spectroscopic, electrochemical measurements and a set of theoretical calculations demonstrate that the core-modification of the inner core of rubyrins has a large influence on the electronic structure. Colorimetric changes are observe that demonstrate that these core-modified rubyrins could be used as selective Hg2+ ion sensors. These properties can be fine-tuned by introducing lipophilic substituents on the meso-aryl rings.
- Full Text:
- Date Issued: 2018
Challenges hindering the implementation of quality supervision in primary health care facilities in Oliver Reginald Tambo District, Eastern Cape Province
- Zamxaka, Nontlantla Caroline
- Authors: Zamxaka, Nontlantla Caroline
- Date: 2018
- Subjects: Hospitals -- Administration , Health services administration , Hospitals -- Business management
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/29256 , vital:77707
- Description: The study investigated the factors that prevent quality supervision in primary health care(PHC) facilities in Oliver Reginald Tambo (O.R. Tambo) district of the Eastern Cape Province of South Africa. The motivation for this study was a concern regarding consistently poor performance by PHC facilities in the province despite regular supervisory visits. The objectives of the study were to explore practices of PHC supervisors in implementing supervision, and to assess perceptions, opinions, and attitudes of PHC supervisors and PHC operational managers with regards to PHC supervisory visits. On search methodology, qualitative approach was predominating whilst quantitative data was supplementing the study. A purposive sample of PHC supervisors and operational managers was drawn from PHC facilities which had a consistent, 100% rate of supervisory visits. The data was analysed thematically. The results revealed systemic and structural challenges that affect the implementation of quality supervision, rendering supervisory visits inefficient. These were: a high workload resulting from inconsistency in the allocation of facilities, as well as the many other responsibilities which supervisors have; a lack of knowledge and experience in supervisors; a lack of health service resources including transport; a high turnover of nurses; lack of support from the district and sub-district leadership and management; lack of collaboration, coordination and integration of activities; and delayed procurement processes resulting in a recurring lack of equipment and medical supplies. The findings of the study brought an understanding of the systemic and structural requirements that need to be made for a functioning quality supervisory system. Successful interventions require strengthening of leadership and governance, and the diligent application of the systems approach to solving problems at facility, district and provincial level. An improvement in leadership and governance should include innovative strategies to utilise the limited resources available without compromising the key objective of quality health care. , Thesis (MPH) -- Faculty of Health Sciences, 2018
- Full Text:
- Date Issued: 2018
- Authors: Zamxaka, Nontlantla Caroline
- Date: 2018
- Subjects: Hospitals -- Administration , Health services administration , Hospitals -- Business management
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/29256 , vital:77707
- Description: The study investigated the factors that prevent quality supervision in primary health care(PHC) facilities in Oliver Reginald Tambo (O.R. Tambo) district of the Eastern Cape Province of South Africa. The motivation for this study was a concern regarding consistently poor performance by PHC facilities in the province despite regular supervisory visits. The objectives of the study were to explore practices of PHC supervisors in implementing supervision, and to assess perceptions, opinions, and attitudes of PHC supervisors and PHC operational managers with regards to PHC supervisory visits. On search methodology, qualitative approach was predominating whilst quantitative data was supplementing the study. A purposive sample of PHC supervisors and operational managers was drawn from PHC facilities which had a consistent, 100% rate of supervisory visits. The data was analysed thematically. The results revealed systemic and structural challenges that affect the implementation of quality supervision, rendering supervisory visits inefficient. These were: a high workload resulting from inconsistency in the allocation of facilities, as well as the many other responsibilities which supervisors have; a lack of knowledge and experience in supervisors; a lack of health service resources including transport; a high turnover of nurses; lack of support from the district and sub-district leadership and management; lack of collaboration, coordination and integration of activities; and delayed procurement processes resulting in a recurring lack of equipment and medical supplies. The findings of the study brought an understanding of the systemic and structural requirements that need to be made for a functioning quality supervisory system. Successful interventions require strengthening of leadership and governance, and the diligent application of the systems approach to solving problems at facility, district and provincial level. An improvement in leadership and governance should include innovative strategies to utilise the limited resources available without compromising the key objective of quality health care. , Thesis (MPH) -- Faculty of Health Sciences, 2018
- Full Text:
- Date Issued: 2018
Electrocatalytic activity of a push-pull phthalocyanine in the presence of reduced and amino functionalized graphene quantum dots towards the electrooxidation of hydrazine
- Centane, Sixolile, Sekhosana, Kutloano E, Matshitse, Refilwe, Nyokong, Tebello
- Authors: Centane, Sixolile , Sekhosana, Kutloano E , Matshitse, Refilwe , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/233456 , vital:50092 , xlink:href="https://doi.org/10.1016/j.jelechem.2018.05.005"
- Description: We report on the electrochemical behaviour of reduced graphene quantum dots (rGQDs) compared to amino functionalized graphene quantum dots (NH2GQDs). Reduction of the GQDs entails the elimination of the excessive carboxyl and hydrogen groups on the GQDs surface, thereby reducing the energy band gap. The energy band gap of graphene is directly proportional to the available oxygen atoms. The two GQD types were conjugated to a novel cobalt phthalocyanine (cobalt tris-(tert-butyl phenoxy)-mono-carboxyphenoxy phthalocyanine, CoPc) via covalent and nom-covalent interactions. The resulting conjugates were tested towards the electrooxidation of hydrazine. The conjugates are represented as rGQDs(π)CoPc, NH2(π)CoPc, rGQDs@CoPc and NH2GQDs@CoPc. The resulting conjugates were adsorbed onto a glassy carbon electrode using the drop and dry method. The lowest limit of detection (LOD) was obtained for rGQDs(π)CoPc.
- Full Text:
- Date Issued: 2018
- Authors: Centane, Sixolile , Sekhosana, Kutloano E , Matshitse, Refilwe , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/233456 , vital:50092 , xlink:href="https://doi.org/10.1016/j.jelechem.2018.05.005"
- Description: We report on the electrochemical behaviour of reduced graphene quantum dots (rGQDs) compared to amino functionalized graphene quantum dots (NH2GQDs). Reduction of the GQDs entails the elimination of the excessive carboxyl and hydrogen groups on the GQDs surface, thereby reducing the energy band gap. The energy band gap of graphene is directly proportional to the available oxygen atoms. The two GQD types were conjugated to a novel cobalt phthalocyanine (cobalt tris-(tert-butyl phenoxy)-mono-carboxyphenoxy phthalocyanine, CoPc) via covalent and nom-covalent interactions. The resulting conjugates were tested towards the electrooxidation of hydrazine. The conjugates are represented as rGQDs(π)CoPc, NH2(π)CoPc, rGQDs@CoPc and NH2GQDs@CoPc. The resulting conjugates were adsorbed onto a glassy carbon electrode using the drop and dry method. The lowest limit of detection (LOD) was obtained for rGQDs(π)CoPc.
- Full Text:
- Date Issued: 2018
Police and community trust in an organisation in transition: the case of Mbare-Musika metropolitan province of Zimbabwe
- Authors: Singende, Matilda
- Date: 2018
- Subjects: Police-community relations , Law enforcement , Community policing
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/29365 , vital:77956
- Description: The focus of this study was to explore the relationship between the police and the community in terms of trust considering that the Zimbabwe Republic Police is in transition. Underpinned by the Procedural Justice Theory and the Social Exchange Theory, the study used a mixed methods approach. The sample was stratified and purposefully drawn from the community and the police respectively. Focus groups were carried out with 30 police officers of the rank of sergeant and constable. The questionnaires were administered to 200 members of the Mbare-Musika community, who were stratified as touts, bus drivers, commuter omnibus drivers, vendors and residents who spent most of their time in the market and around the Mbare termini. Ten (10) interviews were carried out with key informants from the chosen strata. Qualitative data were analysed through thematic data analysis and quantitative data were analysed using the Statistical Package for Social Science (SPSS). The major findings were that the police and the community in Mbare have challenges in terms of trust in their relationship. Crime was found to be on the increase despite efforts made to reduce it. Corruption was found to be rampant in society and in the organisation too although the Mbare community legitimise the police as they cooperate with them, comply with police orders and obey the law. The study recommends that the police be funded to allow them to boost their human and material resources. This in turn will help to improve and increase their training and education programmes in different areas including those that build, enhance and maintain trust. This will also allow the police to meet set standards and keep promises which were endorsed in the Client Service Charter. A model of enhancing trust was suggested. , Thesis (PhD) -- Faculty of Social Sciences and Humanities, 2018
- Full Text:
- Date Issued: 2018
- Authors: Singende, Matilda
- Date: 2018
- Subjects: Police-community relations , Law enforcement , Community policing
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/29365 , vital:77956
- Description: The focus of this study was to explore the relationship between the police and the community in terms of trust considering that the Zimbabwe Republic Police is in transition. Underpinned by the Procedural Justice Theory and the Social Exchange Theory, the study used a mixed methods approach. The sample was stratified and purposefully drawn from the community and the police respectively. Focus groups were carried out with 30 police officers of the rank of sergeant and constable. The questionnaires were administered to 200 members of the Mbare-Musika community, who were stratified as touts, bus drivers, commuter omnibus drivers, vendors and residents who spent most of their time in the market and around the Mbare termini. Ten (10) interviews were carried out with key informants from the chosen strata. Qualitative data were analysed through thematic data analysis and quantitative data were analysed using the Statistical Package for Social Science (SPSS). The major findings were that the police and the community in Mbare have challenges in terms of trust in their relationship. Crime was found to be on the increase despite efforts made to reduce it. Corruption was found to be rampant in society and in the organisation too although the Mbare community legitimise the police as they cooperate with them, comply with police orders and obey the law. The study recommends that the police be funded to allow them to boost their human and material resources. This in turn will help to improve and increase their training and education programmes in different areas including those that build, enhance and maintain trust. This will also allow the police to meet set standards and keep promises which were endorsed in the Client Service Charter. A model of enhancing trust was suggested. , Thesis (PhD) -- Faculty of Social Sciences and Humanities, 2018
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- Date Issued: 2018