Synthesis of molecularly imprinted polymer for selective solid-phase extraction of Salbutamol from urine samples
- Mohammadi, Ali, Alizadeh, Taher, Dinarvand, Rassoul, Ganjali, Mohammed M, Walker, Roderick B
- Authors: Mohammadi, Ali , Alizadeh, Taher , Dinarvand, Rassoul , Ganjali, Mohammed M , Walker, Roderick B
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6410 , http://hdl.handle.net/10962/d1006496
- Description: A highly selective methacrylic based molecularly imprinted polymer (MIP) was synthesized and applied for the separation and the pre-concentration of salbutamol in urine samples. Spectrophotometric determination of salbutamol was achieved using 2,6-dichloroquinone chlorimide as colorimetric reagent. The detection limit of the method was ca. 13 ng/mL in urine after pre-concentration of the samples by MIP-SPE andanalysis with an optimized and sensitive spectrophotometric method. The linear dynamic range for salbutamol determination in urine was 0.04-0.75 μg mL-1. The recovery for the affinity based solid-phase extraction (SPE) with the MIP was more than 96 %.
- Full Text:
- Date Issued: 2009
- Authors: Mohammadi, Ali , Alizadeh, Taher , Dinarvand, Rassoul , Ganjali, Mohammed M , Walker, Roderick B
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6410 , http://hdl.handle.net/10962/d1006496
- Description: A highly selective methacrylic based molecularly imprinted polymer (MIP) was synthesized and applied for the separation and the pre-concentration of salbutamol in urine samples. Spectrophotometric determination of salbutamol was achieved using 2,6-dichloroquinone chlorimide as colorimetric reagent. The detection limit of the method was ca. 13 ng/mL in urine after pre-concentration of the samples by MIP-SPE andanalysis with an optimized and sensitive spectrophotometric method. The linear dynamic range for salbutamol determination in urine was 0.04-0.75 μg mL-1. The recovery for the affinity based solid-phase extraction (SPE) with the MIP was more than 96 %.
- Full Text:
- Date Issued: 2009
Synthesis, spectroscopic and electrochemical properties of manganese, nickel and iron octakis-(2-diethylaminoethanethiol)-phthalocyanine
- Adebayo, A I, Nyokong, Tebello
- Authors: Adebayo, A I , Nyokong, Tebello
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6563 , http://hdl.handle.net/10962/d1004122
- Description: The syntheses, spectroscopic and electrochemical properties of manganese (3), nickel (4) and iron (5) phthalocyanine complexes, octa-substituted at the peripheral positions with diethlyaminoethanethiol substituent, are reported. The electrochemistry of these complexes and the corresponding cobalt complex (6) are reported. Complex 3 showed two reversible reduction couples attributed to the MnIIIPc−2/MnIIPc−2 (E½ = −0.12 V versus Ag|AgCl) and MnIIPc−2/MnIIPc−3 (E½ = −0.82 V versus Ag|AgCl) species. Two ring-based reduction couples were also observed for complex 4. Two reduction couples, assigned to the FeIIPc−2/FeIPc−2 (E½ = −0.35 V versus Ag|AgCl) and FeIPc−2/FeIPc−3 (E½ = −0.96 V versus Ag|AgCl) species, and an oxidation couple, attributed to FeIIIPc−2/FeIIPc−2 (E½ = 0.26 V versus Ag|AgCl) species, were observed. For complex 6, two reductions and one oxidation were also observed with the potential range of 1.2 to −1.8 V versus Ag|AgCl Spectroelectrochemical studies were used to confirm some of the assigned processes.
- Full Text:
- Date Issued: 2009
- Authors: Adebayo, A I , Nyokong, Tebello
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6563 , http://hdl.handle.net/10962/d1004122
- Description: The syntheses, spectroscopic and electrochemical properties of manganese (3), nickel (4) and iron (5) phthalocyanine complexes, octa-substituted at the peripheral positions with diethlyaminoethanethiol substituent, are reported. The electrochemistry of these complexes and the corresponding cobalt complex (6) are reported. Complex 3 showed two reversible reduction couples attributed to the MnIIIPc−2/MnIIPc−2 (E½ = −0.12 V versus Ag|AgCl) and MnIIPc−2/MnIIPc−3 (E½ = −0.82 V versus Ag|AgCl) species. Two ring-based reduction couples were also observed for complex 4. Two reduction couples, assigned to the FeIIPc−2/FeIPc−2 (E½ = −0.35 V versus Ag|AgCl) and FeIPc−2/FeIPc−3 (E½ = −0.96 V versus Ag|AgCl) species, and an oxidation couple, attributed to FeIIIPc−2/FeIIPc−2 (E½ = 0.26 V versus Ag|AgCl) species, were observed. For complex 6, two reductions and one oxidation were also observed with the potential range of 1.2 to −1.8 V versus Ag|AgCl Spectroelectrochemical studies were used to confirm some of the assigned processes.
- Full Text:
- Date Issued: 2009
Taking education and training to higher levels
- Authors: Phiri, Aretha
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:7203 , http://hdl.handle.net/10962/d1006400
- Description: Professor Tebello Nyokong of the Chemistry Department has won yet another prestigious award. She was voted "the most influential women in business and government" in the category of education and training, in an event sponsored by CEO Magazine.
- Full Text:
- Date Issued: 2009
- Authors: Phiri, Aretha
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:7203 , http://hdl.handle.net/10962/d1006400
- Description: Professor Tebello Nyokong of the Chemistry Department has won yet another prestigious award. She was voted "the most influential women in business and government" in the category of education and training, in an event sponsored by CEO Magazine.
- Full Text:
- Date Issued: 2009
The ataxia protein sacsin is a functional co-chaperone that protects against polyglutamine-expanded ataxin-1
- Parfitt, David A, Michael, Gregory J, Vermeulen, Esmeralda G M, Prodromou, Natalia V, Webb, Tom R, Gallo, Jean-Marc, Cheetham, Michael E, Nicoll, William S, Blatch, Gregory L, Chapple, J Paul
- Authors: Parfitt, David A , Michael, Gregory J , Vermeulen, Esmeralda G M , Prodromou, Natalia V , Webb, Tom R , Gallo, Jean-Marc , Cheetham, Michael E , Nicoll, William S , Blatch, Gregory L , Chapple, J Paul
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6485 , http://hdl.handle.net/10962/d1006262 , http://hmg.oxfordjournals.org/content/18/9/1556
- Description: An extensive protein–protein interaction network has been identified between proteins implicated in inherited ataxias. The protein sacsin, which is mutated in the early-onset neurodegenerative disease autosomal recessive spastic ataxia of Charlevoix-Saguenay, is a node in this interactome. Here, we have established the neuronal expression of sacsin and functionally characterized domains of the 4579 amino acid protein. Sacsin is most highly expressed in large neurons, particularly within brain motor systems, including cerebellar Purkinje cells. Its subcellular localization in SH-SY5Y neuroblastoma cells was predominantly cytoplasmic with a mitochondrial component. We identified a putative ubiquitin-like (UbL) domain at the N-terminus of sacsin and demonstrated an interaction with the proteasome. Furthermore, sacsin contains a predicted J-domain, the defining feature of DnaJ/Hsp40 proteins. Using a bacterial complementation assay, the sacsin J-domain was demonstrated to be functional. The presence of both UbL and J-domains in sacsin suggests that it may integrate the ubiquitin–proteasome system and Hsp70 function to a specific cellular role. The Hsp70 chaperone machinery is an important component of the cellular response towards aggregation prone mutant proteins that are associated with neurodegenerative diseases. We therefore investigated the effects of siRNA-mediated sacsin knockdown on polyglutamine-expanded ataxin-1. Importantly, SACS siRNA did not affect cell viability with GFP-ataxin-1[30Q], but enhanced the toxicity of GFP-ataxin- 1[82Q], suggesting that sacsin is protective against mutant ataxin-1. Thus, sacsin is an ataxia protein and a regulator of the Hsp70 chaperone machinery that is implicated in the processing of other ataxialinked proteins.
- Full Text:
- Date Issued: 2009
- Authors: Parfitt, David A , Michael, Gregory J , Vermeulen, Esmeralda G M , Prodromou, Natalia V , Webb, Tom R , Gallo, Jean-Marc , Cheetham, Michael E , Nicoll, William S , Blatch, Gregory L , Chapple, J Paul
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6485 , http://hdl.handle.net/10962/d1006262 , http://hmg.oxfordjournals.org/content/18/9/1556
- Description: An extensive protein–protein interaction network has been identified between proteins implicated in inherited ataxias. The protein sacsin, which is mutated in the early-onset neurodegenerative disease autosomal recessive spastic ataxia of Charlevoix-Saguenay, is a node in this interactome. Here, we have established the neuronal expression of sacsin and functionally characterized domains of the 4579 amino acid protein. Sacsin is most highly expressed in large neurons, particularly within brain motor systems, including cerebellar Purkinje cells. Its subcellular localization in SH-SY5Y neuroblastoma cells was predominantly cytoplasmic with a mitochondrial component. We identified a putative ubiquitin-like (UbL) domain at the N-terminus of sacsin and demonstrated an interaction with the proteasome. Furthermore, sacsin contains a predicted J-domain, the defining feature of DnaJ/Hsp40 proteins. Using a bacterial complementation assay, the sacsin J-domain was demonstrated to be functional. The presence of both UbL and J-domains in sacsin suggests that it may integrate the ubiquitin–proteasome system and Hsp70 function to a specific cellular role. The Hsp70 chaperone machinery is an important component of the cellular response towards aggregation prone mutant proteins that are associated with neurodegenerative diseases. We therefore investigated the effects of siRNA-mediated sacsin knockdown on polyglutamine-expanded ataxin-1. Importantly, SACS siRNA did not affect cell viability with GFP-ataxin-1[30Q], but enhanced the toxicity of GFP-ataxin- 1[82Q], suggesting that sacsin is protective against mutant ataxin-1. Thus, sacsin is an ataxia protein and a regulator of the Hsp70 chaperone machinery that is implicated in the processing of other ataxialinked proteins.
- Full Text:
- Date Issued: 2009
The evaluation of Eudragit microcapsules manufactured by solvent evaporation using USP Apparatus 1
- Khamanga, Sandile M, Parfitt, Natalie R, Nyamuzhiwa, Tsitsi, Haidula, Hendrina, Walker, Roderick B
- Authors: Khamanga, Sandile M , Parfitt, Natalie R , Nyamuzhiwa, Tsitsi , Haidula, Hendrina , Walker, Roderick B
- Date: 2009
- Language: English
- Type: text , Article
- Identifier: vital:6389 , http://hdl.handle.net/10962/d1006310
- Description: The objectives of this study were to prepare microcapsules containing verapamil and propranolol and to evaluate the kinetics and mechanism of drug release from the microcapsules using USP Apparatus 1. The effects of polymer concentration and polymer type on the cumulative amount of drug released were evaluated. The microcapsules were manufactured using Eudragit RS and RL polymers by solvent evaporation with the ultimate aim of prolonging drug release. Twenty-four formulations were prepared using different drug/polymer ratios. The effects of polymer type and polymer/drug ratios on the size, flow properties, surface morphology, and the release characteristics of the microcapsules were examined. The effects of drug inclusion methods on drug loading, encapsulation efficiency, and release properties of the complex microcapsules were also investigated. The formulations containing drug/polymer ratio 1:4 (w/w) were the most appropriate with respect to encapsulation efficiency (70%), flow properties (HR = 1.2), drug loading (15–20%), and drug release characteristics, in all cases. The release kinetics from the different formulations followed mainly a diffusion-controlled mechanism.
- Full Text:
- Date Issued: 2009
- Authors: Khamanga, Sandile M , Parfitt, Natalie R , Nyamuzhiwa, Tsitsi , Haidula, Hendrina , Walker, Roderick B
- Date: 2009
- Language: English
- Type: text , Article
- Identifier: vital:6389 , http://hdl.handle.net/10962/d1006310
- Description: The objectives of this study were to prepare microcapsules containing verapamil and propranolol and to evaluate the kinetics and mechanism of drug release from the microcapsules using USP Apparatus 1. The effects of polymer concentration and polymer type on the cumulative amount of drug released were evaluated. The microcapsules were manufactured using Eudragit RS and RL polymers by solvent evaporation with the ultimate aim of prolonging drug release. Twenty-four formulations were prepared using different drug/polymer ratios. The effects of polymer type and polymer/drug ratios on the size, flow properties, surface morphology, and the release characteristics of the microcapsules were examined. The effects of drug inclusion methods on drug loading, encapsulation efficiency, and release properties of the complex microcapsules were also investigated. The formulations containing drug/polymer ratio 1:4 (w/w) were the most appropriate with respect to encapsulation efficiency (70%), flow properties (HR = 1.2), drug loading (15–20%), and drug release characteristics, in all cases. The release kinetics from the different formulations followed mainly a diffusion-controlled mechanism.
- Full Text:
- Date Issued: 2009
The KwaZulu-Natal Slums Act: bloody legislation against the expropriated
- Authors: Pithouse, Richard, 1970-
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6201 , http://hdl.handle.net/10962/d1008568
- Description: [From introduction]: On 14 May 2009 the Constitutional Court will hear the attempt by the shack dweller’s movement Abahlali baseMjondolo to have the KwaZulu-Natal Slums Act declared unlawful. Other provinces have been mandated to develop similar legislation and the decision of the court may have a significant impact on the future of our cities.
- Full Text:
- Date Issued: 2009
- Authors: Pithouse, Richard, 1970-
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6201 , http://hdl.handle.net/10962/d1008568
- Description: [From introduction]: On 14 May 2009 the Constitutional Court will hear the attempt by the shack dweller’s movement Abahlali baseMjondolo to have the KwaZulu-Natal Slums Act declared unlawful. Other provinces have been mandated to develop similar legislation and the decision of the court may have a significant impact on the future of our cities.
- Full Text:
- Date Issued: 2009
The thoroughly democratic logic of refusing to vote
- Authors: Pithouse, Richard, 1970-
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6202 , http://hdl.handle.net/10962/d1008570
- Description: [From introduction]: Poor people’s movements like the Landless People’s Movement in Johannesburg, the Anti-Eviction Campaign in Cape Town and Abahlali baseMjondolo in Durban and Cape Town, along with a host of smaller community organisations around the country, have announced their refusal to vote in the coming election.
- Full Text:
- Date Issued: 2009
- Authors: Pithouse, Richard, 1970-
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6202 , http://hdl.handle.net/10962/d1008570
- Description: [From introduction]: Poor people’s movements like the Landless People’s Movement in Johannesburg, the Anti-Eviction Campaign in Cape Town and Abahlali baseMjondolo in Durban and Cape Town, along with a host of smaller community organisations around the country, have announced their refusal to vote in the coming election.
- Full Text:
- Date Issued: 2009
The TPR2B domain of the Hsp70/Hsp90 organizing protein (Hop) may contribute towards its dimerization
- Longshaw, Victoria M, Stephens, Linda L, Daniel, Sheril, Blatch, Gregory L
- Authors: Longshaw, Victoria M , Stephens, Linda L , Daniel, Sheril , Blatch, Gregory L
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6481 , http://hdl.handle.net/10962/d1006253 , http://dx.doi.org/10.2174/092986609787848162
- Description: The role of the TPR2B domain of Hop is as yet unknown. We have shown here by site directed mutagenesis and size exclusion chromatography for the first time that the TPR1 and TPR2B domains of Hop independently dimerized, and that the dimerization of TPR2B was not dependent on its predicted two-carboxylate clamp residues. Furthermore, our data indicated that the dimerization of Hop and its domains was not disrupted in the presence of Hsp70 and Hsp90 peptides.
- Full Text:
- Date Issued: 2009
The TPR2B domain of the Hsp70/Hsp90 organizing protein (Hop) may contribute towards its dimerization
- Authors: Longshaw, Victoria M , Stephens, Linda L , Daniel, Sheril , Blatch, Gregory L
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6481 , http://hdl.handle.net/10962/d1006253 , http://dx.doi.org/10.2174/092986609787848162
- Description: The role of the TPR2B domain of Hop is as yet unknown. We have shown here by site directed mutagenesis and size exclusion chromatography for the first time that the TPR1 and TPR2B domains of Hop independently dimerized, and that the dimerization of TPR2B was not dependent on its predicted two-carboxylate clamp residues. Furthermore, our data indicated that the dimerization of Hop and its domains was not disrupted in the presence of Hsp70 and Hsp90 peptides.
- Full Text:
- Date Issued: 2009
The transportability and utility of cognitive therapy in South African contexts: a review
- Authors: Young, Charles
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6279 , http://hdl.handle.net/10962/d1008280
- Description: Cognitive therapy could be more widely promoted in South Africa given the great disparity between the need and provision of psychological therapies. Three possible objections to the promotion of cognitive therapy are considered: uncertainty surrounding the effectiveness of cognitive therapy in South African contexts; uncertainty surrounding the applicability in multicultural contexts; and suggestions that cognitive therapy is decontextualised and therefore objectionable in a country facing major social challenges. A systematic review of the literature indentified 15 outcome studies, and suggests that cognitive therapy is a viable and much-needed approach in South Africa.
- Full Text:
- Date Issued: 2009
- Authors: Young, Charles
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6279 , http://hdl.handle.net/10962/d1008280
- Description: Cognitive therapy could be more widely promoted in South Africa given the great disparity between the need and provision of psychological therapies. Three possible objections to the promotion of cognitive therapy are considered: uncertainty surrounding the effectiveness of cognitive therapy in South African contexts; uncertainty surrounding the applicability in multicultural contexts; and suggestions that cognitive therapy is decontextualised and therefore objectionable in a country facing major social challenges. A systematic review of the literature indentified 15 outcome studies, and suggests that cognitive therapy is a viable and much-needed approach in South Africa.
- Full Text:
- Date Issued: 2009
The WHO UNESCO FIP Pharmacy Education Taskforce (commentary)
- Anderson, Claire, Bates, Ian, Beck, Diane, Penick Brock, Tina, Futter, William T, Mercer, Hugo, Rouse, Mike, Whitmarsh, Sarah, Wuliji, Tana, Yonemura, Akemi
- Authors: Anderson, Claire , Bates, Ian , Beck, Diane , Penick Brock, Tina , Futter, William T , Mercer, Hugo , Rouse, Mike , Whitmarsh, Sarah , Wuliji, Tana , Yonemura, Akemi
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6347 , http://hdl.handle.net/10962/d1006020
- Description: Pharmacists' roles are evolving from that of compounders and dispensers of medicines to that of experts on medicines within multidisciplinary health care teams. In the developing country context, the pharmacy is often the most accessible or even the sole point of access to health care advice and services. Because of their knowledge of medicines and clinical therapeutics, pharmacists are suitably placed for task shifting in health care and could be further trained to undertake functions such as clinical management and laboratory diagnostics. Indeed, pharmacists have been shown to be willing, competent, and cost-effective providers of what the professional literature calls "pharmaceutical care interventions"; however, internationally, there is an underuse of pharmacists for patient care and public health efforts. A coordinated and multifaceted effort to advance workforce planning, training and education is needed in order to prepare an adequate number of well-trained pharmacists for such roles. Acknowledging that health care needs can vary across geography and culture, an international group of key stakeholders in pharmacy education and global health has reached unanimous agreement that pharmacy education must be quality-driven and directed towards societal health care needs, the services required to meet those needs, the competences necessary to provide these services and the education needed to ensure those competences. Using that framework, this commentary describes the Pharmacy Education Taskforce of the World Health Organization, United Nations Educational, Scientific and Cultural Organization and the International Pharmaceutical Federation Global Pharmacy and the Education Action Plan 2008–2010, including the foundation, domains, objectives and outcome measures, and includes several examples of current activities within this scope.
- Full Text:
- Date Issued: 2009
- Authors: Anderson, Claire , Bates, Ian , Beck, Diane , Penick Brock, Tina , Futter, William T , Mercer, Hugo , Rouse, Mike , Whitmarsh, Sarah , Wuliji, Tana , Yonemura, Akemi
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6347 , http://hdl.handle.net/10962/d1006020
- Description: Pharmacists' roles are evolving from that of compounders and dispensers of medicines to that of experts on medicines within multidisciplinary health care teams. In the developing country context, the pharmacy is often the most accessible or even the sole point of access to health care advice and services. Because of their knowledge of medicines and clinical therapeutics, pharmacists are suitably placed for task shifting in health care and could be further trained to undertake functions such as clinical management and laboratory diagnostics. Indeed, pharmacists have been shown to be willing, competent, and cost-effective providers of what the professional literature calls "pharmaceutical care interventions"; however, internationally, there is an underuse of pharmacists for patient care and public health efforts. A coordinated and multifaceted effort to advance workforce planning, training and education is needed in order to prepare an adequate number of well-trained pharmacists for such roles. Acknowledging that health care needs can vary across geography and culture, an international group of key stakeholders in pharmacy education and global health has reached unanimous agreement that pharmacy education must be quality-driven and directed towards societal health care needs, the services required to meet those needs, the competences necessary to provide these services and the education needed to ensure those competences. Using that framework, this commentary describes the Pharmacy Education Taskforce of the World Health Organization, United Nations Educational, Scientific and Cultural Organization and the International Pharmaceutical Federation Global Pharmacy and the Education Action Plan 2008–2010, including the foundation, domains, objectives and outcome measures, and includes several examples of current activities within this scope.
- Full Text:
- Date Issued: 2009
Topographic thresholds in gully development on the hillslopes of communal areas in Ngqushwa Local Municipality, Eastern Cape, South Africa
- Kakembo, V, Xanga, W W, Rowntree, Kate M
- Authors: Kakembo, V , Xanga, W W , Rowntree, Kate M
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6691 , http://hdl.handle.net/10962/d1006726
- Description: The relationships between the spatial distribution of gully erosion and topographic thresholds in the form of slope angle, position and configuration, as well as land use change in the form of abandoned lands were examined in several affected catchments of the Eastern Cape Province, South Africa. Land use and permanent gullies were mapped, digitized from orthophoto maps in Arc/info 3.5.2 GIS and converted to shapefiles using ArcView 3.2 GIS. Relationships between the mapped phenomena and topographic variables were sought using a Digital Elevation Model (DEM) in Idrisi Kilimanjaro GIS. A comparison between areas with a high potential for gullying and actual gully erosion was made using the Stream Power Index (SPI) as a surrogate for critical flow shear stress. Field surveys were also conducted to assess the present condition of the gullied sites as well as to validate DEM derivations. Seventy five percent of the gullied area was noted to lie on abandoned lands. A predominance of gullying in concave bottom lands was also identified. The SPI values highlighted a distinct preferential topographic zone for gully location. A conceptual model depicting the interaction between land use and topographic parameters to induce gully erosion was developed. This should assist local authorities to develop a policy regarding management of abandoned lands.
- Full Text:
- Date Issued: 2009
- Authors: Kakembo, V , Xanga, W W , Rowntree, Kate M
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6691 , http://hdl.handle.net/10962/d1006726
- Description: The relationships between the spatial distribution of gully erosion and topographic thresholds in the form of slope angle, position and configuration, as well as land use change in the form of abandoned lands were examined in several affected catchments of the Eastern Cape Province, South Africa. Land use and permanent gullies were mapped, digitized from orthophoto maps in Arc/info 3.5.2 GIS and converted to shapefiles using ArcView 3.2 GIS. Relationships between the mapped phenomena and topographic variables were sought using a Digital Elevation Model (DEM) in Idrisi Kilimanjaro GIS. A comparison between areas with a high potential for gullying and actual gully erosion was made using the Stream Power Index (SPI) as a surrogate for critical flow shear stress. Field surveys were also conducted to assess the present condition of the gullied sites as well as to validate DEM derivations. Seventy five percent of the gullied area was noted to lie on abandoned lands. A predominance of gullying in concave bottom lands was also identified. The SPI values highlighted a distinct preferential topographic zone for gully location. A conceptual model depicting the interaction between land use and topographic parameters to induce gully erosion was developed. This should assist local authorities to develop a policy regarding management of abandoned lands.
- Full Text:
- Date Issued: 2009
Towards a GPS-based TEC prediction model for Southern Africa with feed forward networks
- Habarulema, John B, McKinnell, Lee-Anne, Opperman, Ben D L
- Authors: Habarulema, John B , McKinnell, Lee-Anne , Opperman, Ben D L
- Date: 2009
- Language: English
- Type: text , Article
- Identifier: vital:6806 , http://hdl.handle.net/10962/d1004192
- Description: In this paper, first results from a national Global Positioning System (GPS) based total electron content (TEC) prediction model over South Africa are presented. Data for 10 GPS receiver stations distributed through out the country were used to train a feed forward neural network (NN) over an interval of at most five years. In the NN training, validating and testing processes, five factors which are well known to influence TEC variability namely diurnal variation, seasonal variation, magnetic activity, solar activity and the geographic position of the GPS receivers were included in the NN model. The database consisted of 1-min data and therefore the NN model developed can be used to forecast TEC values 1 min in advance. Results from the NN national model (NM) were compared with hourly TEC values generated by the earlier developed NN single station models (SSMs) at Sutherland (32.38°S, 20.81°E) and Springbok (29.67°S, 17.88°E), to predict TEC variations over the Cape Town (33.95°S, 18.47°E) and Upington (28.41°S, 21.26°E) stations, respectively, during equinoxes and solstices. This revealed that, on average, the NM led to an improvement in TEC prediction accuracy compared to the SSMs for the considered testing periods.
- Full Text:
- Date Issued: 2009
- Authors: Habarulema, John B , McKinnell, Lee-Anne , Opperman, Ben D L
- Date: 2009
- Language: English
- Type: text , Article
- Identifier: vital:6806 , http://hdl.handle.net/10962/d1004192
- Description: In this paper, first results from a national Global Positioning System (GPS) based total electron content (TEC) prediction model over South Africa are presented. Data for 10 GPS receiver stations distributed through out the country were used to train a feed forward neural network (NN) over an interval of at most five years. In the NN training, validating and testing processes, five factors which are well known to influence TEC variability namely diurnal variation, seasonal variation, magnetic activity, solar activity and the geographic position of the GPS receivers were included in the NN model. The database consisted of 1-min data and therefore the NN model developed can be used to forecast TEC values 1 min in advance. Results from the NN national model (NM) were compared with hourly TEC values generated by the earlier developed NN single station models (SSMs) at Sutherland (32.38°S, 20.81°E) and Springbok (29.67°S, 17.88°E), to predict TEC variations over the Cape Town (33.95°S, 18.47°E) and Upington (28.41°S, 21.26°E) stations, respectively, during equinoxes and solstices. This revealed that, on average, the NM led to an improvement in TEC prediction accuracy compared to the SSMs for the considered testing periods.
- Full Text:
- Date Issued: 2009
Treating posttraumatic stress disorder in South Africa : an integrative model grounded in case-based research
- Authors: Edwards, David J A
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6232 , http://hdl.handle.net/10962/d1007782
- Description: The article presents a model for formulating and planning treatment for post-traumatic stress disorder (PTSD) in South Africa derived from the existing literature and in conjunction with a review of a series of studies of cases treated using the guidelines of Ehlers and Clark's cognitive therapy. It is argued that the construction of psychotherapies (or even components of psychotherapy) for PTSD in terms of traditional categories ("psychodynamic", "cognitive-behavioural", "narrative" etc.) is misleading and unhelpful. Instead, superordinate concepts derived from thinking about evidence-based practice provide a more grounded focus on the practical issues faced by therapists treating PTSD. These concepts, which include competences and metcacompetences, therapist responsiveness, stages of therapy and case formulation, provide a basis for a genuinely integrative approach. The proposed model suggests seven broad areas of clinical focus for work with PTSD which can be arranged at three levels of priority: level 1 crisis intervention and stabilization; level 2 promoting engagement with treatment, and level 3 selection, sequencing and timing of active treatment interventions. Material from the case series is used to illustrate the application of the model.
- Full Text:
- Date Issued: 2009
- Authors: Edwards, David J A
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6232 , http://hdl.handle.net/10962/d1007782
- Description: The article presents a model for formulating and planning treatment for post-traumatic stress disorder (PTSD) in South Africa derived from the existing literature and in conjunction with a review of a series of studies of cases treated using the guidelines of Ehlers and Clark's cognitive therapy. It is argued that the construction of psychotherapies (or even components of psychotherapy) for PTSD in terms of traditional categories ("psychodynamic", "cognitive-behavioural", "narrative" etc.) is misleading and unhelpful. Instead, superordinate concepts derived from thinking about evidence-based practice provide a more grounded focus on the practical issues faced by therapists treating PTSD. These concepts, which include competences and metcacompetences, therapist responsiveness, stages of therapy and case formulation, provide a basis for a genuinely integrative approach. The proposed model suggests seven broad areas of clinical focus for work with PTSD which can be arranged at three levels of priority: level 1 crisis intervention and stabilization; level 2 promoting engagement with treatment, and level 3 selection, sequencing and timing of active treatment interventions. Material from the case series is used to illustrate the application of the model.
- Full Text:
- Date Issued: 2009
Tri-locus sequence data reject a Gondwanan origin hypothesis for the African/South Pacific crab genus Hymenosoma
- Teske, Peter R, McLay, Colin L, Sandoval-Castillo, Jonathan, Papadopoulos, Isabelle, Newman, Brent K, Griffiths, Charles L, McQuaid, Christopher D, Barker, Nigel P, Borgonie, Gaetan, Beheregaray, Luciano B
- Authors: Teske, Peter R , McLay, Colin L , Sandoval-Castillo, Jonathan , Papadopoulos, Isabelle , Newman, Brent K , Griffiths, Charles L , McQuaid, Christopher D , Barker, Nigel P , Borgonie, Gaetan , Beheregaray, Luciano B
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6547 , http://hdl.handle.net/10962/d1006003
- Description: Crabs of the family Hymenosomatidae are common in coastal and shelf regions throughout much of the southern hemisphere. One of the genera in the family, Hymenosoma, is represented in Africa and the South Pacific (Australia and New Zealand). This distribution can be explained either by vicariance (presence of the genus on the Gondwanan supercontinent and divergence following its break-up) or more recent transoceanic dispersal from one region to the other. We tested these hypotheses by reconstructing phylogenetic relationships among the seven presently-accepted species in the genus, as well as examining their placement among other hymenosomatid crabs, using sequence data from two nuclear markers (Adenine Nucleotide Transporter [ANT] exon 2 and 18S rDNA) and three mitochondrial markers (COI, 12S and 16S rDNA). The five southern African representatives of the genus were recovered as a monophyletic lineage, and another southern African species, Neorhynchoplax bovis, was identified as their sister taxon. The two species of Hymenosoma from the South Pacific neither clustered with their African congeners, nor with each other, and should therefore both be placed into different genera. Molecular dating supports a post-Gondwanan origin of the Hymenosomatidae. While long-distance dispersal cannot be ruled out to explain the presence of the family Hymenosomatidae on the former Gondwanan land-masses and beyond, the evolutionary history of the African species of Hymenosoma indicates that a third means of speciation may be important in this group: gradual along-coast dispersal from tropical towards temperate regions, with range expansions into formerly inhospitable habitat during warm climatic phases, followed by adaptation and speciation during subsequent cooler phases.
- Full Text:
- Date Issued: 2009
- Authors: Teske, Peter R , McLay, Colin L , Sandoval-Castillo, Jonathan , Papadopoulos, Isabelle , Newman, Brent K , Griffiths, Charles L , McQuaid, Christopher D , Barker, Nigel P , Borgonie, Gaetan , Beheregaray, Luciano B
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6547 , http://hdl.handle.net/10962/d1006003
- Description: Crabs of the family Hymenosomatidae are common in coastal and shelf regions throughout much of the southern hemisphere. One of the genera in the family, Hymenosoma, is represented in Africa and the South Pacific (Australia and New Zealand). This distribution can be explained either by vicariance (presence of the genus on the Gondwanan supercontinent and divergence following its break-up) or more recent transoceanic dispersal from one region to the other. We tested these hypotheses by reconstructing phylogenetic relationships among the seven presently-accepted species in the genus, as well as examining their placement among other hymenosomatid crabs, using sequence data from two nuclear markers (Adenine Nucleotide Transporter [ANT] exon 2 and 18S rDNA) and three mitochondrial markers (COI, 12S and 16S rDNA). The five southern African representatives of the genus were recovered as a monophyletic lineage, and another southern African species, Neorhynchoplax bovis, was identified as their sister taxon. The two species of Hymenosoma from the South Pacific neither clustered with their African congeners, nor with each other, and should therefore both be placed into different genera. Molecular dating supports a post-Gondwanan origin of the Hymenosomatidae. While long-distance dispersal cannot be ruled out to explain the presence of the family Hymenosomatidae on the former Gondwanan land-masses and beyond, the evolutionary history of the African species of Hymenosoma indicates that a third means of speciation may be important in this group: gradual along-coast dispersal from tropical towards temperate regions, with range expansions into formerly inhospitable habitat during warm climatic phases, followed by adaptation and speciation during subsequent cooler phases.
- Full Text:
- Date Issued: 2009
We are all the public
- Authors: Pithouse, Richard, 1970-
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6198 , http://hdl.handle.net/10962/d1008562
- Description: [from introduction]: Across the country the most vulnerable people in our society are being subject to brazenly unlawful and often violent action at the hands of the state. Homeless people, refugees, sex workers, street traders and shack dwellers are all being taught, in the most literal sense of the term, to know their place. But state illegality is not only aimed at the segregation of physical space. It is also about ensuring that the people on the margins of society know their political place.
- Full Text:
- Date Issued: 2009
- Authors: Pithouse, Richard, 1970-
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6198 , http://hdl.handle.net/10962/d1008562
- Description: [from introduction]: Across the country the most vulnerable people in our society are being subject to brazenly unlawful and often violent action at the hands of the state. Homeless people, refugees, sex workers, street traders and shack dwellers are all being taught, in the most literal sense of the term, to know their place. But state illegality is not only aimed at the segregation of physical space. It is also about ensuring that the people on the margins of society know their political place.
- Full Text:
- Date Issued: 2009
We need a conversation about development
- Authors: Pithouse, Richard, 1970-
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6199 , http://hdl.handle.net/10962/d1008563
- Description: [From the introduction] From the Communist Party across to the corporate spin-doctors and down to the Development Committees in the shack settlements, more or less everybody in South Africa speaks the language of development. In some ways this is a good thing. It indicates a hard won agreement that the realities of inequality in our society are so cruel and perverse that any social project can only be credible if it will ameliorate these divisions and the suffering they cause.
- Full Text:
- Date Issued: 2009
- Authors: Pithouse, Richard, 1970-
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6199 , http://hdl.handle.net/10962/d1008563
- Description: [From the introduction] From the Communist Party across to the corporate spin-doctors and down to the Development Committees in the shack settlements, more or less everybody in South Africa speaks the language of development. In some ways this is a good thing. It indicates a hard won agreement that the realities of inequality in our society are so cruel and perverse that any social project can only be credible if it will ameliorate these divisions and the suffering they cause.
- Full Text:
- Date Issued: 2009
Wealth differentiation in household use and trade in non-timber forest products in South Africa
- Paumgarten, Fiona, Shackleton, Charlie M
- Authors: Paumgarten, Fiona , Shackleton, Charlie M
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6646 , http://hdl.handle.net/10962/d1006892
- Description: Findings from southern Africa and internationally indicate the local use and trade of NTFPs to be significant however most present a composite picture, failing to account for intra-community socio-economic differences. These differences may have implications for policy and practice related to poverty alleviation and sustainable use. This paper reports on a study in South Africa which explored the relationship between household wealth and the use, procurement and sale of NTFPs in two villages. There was no influence of wealth on the proportion of households using or purchasing most of the NTFPs, or the number used. However, wealthier households bought significantly more resources per household, and poor households (at one village) sold significantly more. These results are discussed within the context of local conditions and poverty alleviation debates.
- Full Text:
- Date Issued: 2009
- Authors: Paumgarten, Fiona , Shackleton, Charlie M
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6646 , http://hdl.handle.net/10962/d1006892
- Description: Findings from southern Africa and internationally indicate the local use and trade of NTFPs to be significant however most present a composite picture, failing to account for intra-community socio-economic differences. These differences may have implications for policy and practice related to poverty alleviation and sustainable use. This paper reports on a study in South Africa which explored the relationship between household wealth and the use, procurement and sale of NTFPs in two villages. There was no influence of wealth on the proportion of households using or purchasing most of the NTFPs, or the number used. However, wealthier households bought significantly more resources per household, and poor households (at one village) sold significantly more. These results are discussed within the context of local conditions and poverty alleviation debates.
- Full Text:
- Date Issued: 2009
What services and supports are needed to enable trauma survivors to rebuild their lives? Implications of a systematic case study of cognitive therapy with a township adolescent girl with PTSD following rape
- Payne, Charmaine, Edwards, David J A
- Authors: Payne, Charmaine , Edwards, David J A
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6278 , http://hdl.handle.net/10962/d1008279
- Description: This systematic clinical case study describes the psychological assessment and treatment with cognitive therapy of Zanele, a Xhosa-speaking adolescent rape survivor with major depressive disorder and posttraumatic stress disorder (PTSD). A case narrative was developed to document the main features of the therapy process and progress was monitored using scales measuring symptoms of depression and PTSD. The narrative documents the operation in a local context of factors that maintain PTSD that have been identified in the international literature and, with the self-report scales, provides evidence for Zanele’s recovery from PTSD and the transportability to this context of an evidence-based psychological treatment. The narrative also documents the lack of safety for young women and girls in a South African township as well as significant limitations in the professional services available: in this case, Zanele was infected with HIV and other sexually transmitted diseases but medical management had not been followed through, and criminal charges against the rapist were dropped, and dropped again even after he had committed another rape on a six-year-old girl. This provides a basis for examining the complementary roles that can be played by psychologists and other professionals in empowering trauma survivors to regain a sense of dignity and control over their lives.
- Full Text:
- Date Issued: 2009
- Authors: Payne, Charmaine , Edwards, David J A
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6278 , http://hdl.handle.net/10962/d1008279
- Description: This systematic clinical case study describes the psychological assessment and treatment with cognitive therapy of Zanele, a Xhosa-speaking adolescent rape survivor with major depressive disorder and posttraumatic stress disorder (PTSD). A case narrative was developed to document the main features of the therapy process and progress was monitored using scales measuring symptoms of depression and PTSD. The narrative documents the operation in a local context of factors that maintain PTSD that have been identified in the international literature and, with the self-report scales, provides evidence for Zanele’s recovery from PTSD and the transportability to this context of an evidence-based psychological treatment. The narrative also documents the lack of safety for young women and girls in a South African township as well as significant limitations in the professional services available: in this case, Zanele was infected with HIV and other sexually transmitted diseases but medical management had not been followed through, and criminal charges against the rapist were dropped, and dropped again even after he had committed another rape on a six-year-old girl. This provides a basis for examining the complementary roles that can be played by psychologists and other professionals in empowering trauma survivors to regain a sense of dignity and control over their lives.
- Full Text:
- Date Issued: 2009
Who uses the fishery resources in South Africa’s largest impoundment? Characterising subsistence and recreational fishing sectors on Lake Gariep
- Ellender, Bruce R, Weyl, Olaf L F, Winker, A Henning
- Authors: Ellender, Bruce R , Weyl, Olaf L F , Winker, A Henning
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6778 , http://hdl.handle.net/10962/d1008088
- Description: The African Union’s prioritisation of inland fisheries as an investment area for poverty alleviation and regional economic development will require the development of management plans. These should be based on sound knowledge of the social dynamics of the resource users. In South Africa the social dynamics of resource users of inland fisheries have never been assessed. The purpose of this study was to assess the human dimensions of the anglers utilising the fishery in Lake Gariep, South Africa’s largest impoundment. The study was based on 357 first-time interviews conducted on the lakeshore between October 2006 and December 2007. Anglers were categorised as recreational (39%) or subsistence (61%) based on their residency, occupation, primary motivation for angling, mode of transport and gear use. Subsistence anglers were local (99%), residing within 10 km of the place where they were interviewed, while recreational anglers included both local resident and non-resident members. The racial composition of anglers was dependent on user group and differed significantly (p ≤ 0.05) from the demographic composition of the regional population. Recreational anglers were predominantly White (≥ 60% of interviews) and Coloured (≥ 25%), while 84% of subsistence anglers were Coloured and 16% Black African. Most recreational anglers had permanent employment or were pensioners while <30% of subsistence anglers were permanently employed. Most recreational users (82%) accessed the lake with their own vehicle while subsistence anglers mainly walked (63%) or used a bicycle (28%). Recreational interviewees either consumed (59%), sold (11%), gave away (10%) or released (20%) some of their catch. Subsistence anglers either ate their catch (53%) and/or sold (41%) their catch. Within the subsistence sector no anglers released fish after capture or gave some of the catch away. We conclude that this inland fishery contributes to the livelihood of the rural poor who use the lake on a subsistence basis and that recreational-angler based tourism may contribute to increased income and employment opportunities through related service industries.
- Full Text:
- Date Issued: 2009
- Authors: Ellender, Bruce R , Weyl, Olaf L F , Winker, A Henning
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6778 , http://hdl.handle.net/10962/d1008088
- Description: The African Union’s prioritisation of inland fisheries as an investment area for poverty alleviation and regional economic development will require the development of management plans. These should be based on sound knowledge of the social dynamics of the resource users. In South Africa the social dynamics of resource users of inland fisheries have never been assessed. The purpose of this study was to assess the human dimensions of the anglers utilising the fishery in Lake Gariep, South Africa’s largest impoundment. The study was based on 357 first-time interviews conducted on the lakeshore between October 2006 and December 2007. Anglers were categorised as recreational (39%) or subsistence (61%) based on their residency, occupation, primary motivation for angling, mode of transport and gear use. Subsistence anglers were local (99%), residing within 10 km of the place where they were interviewed, while recreational anglers included both local resident and non-resident members. The racial composition of anglers was dependent on user group and differed significantly (p ≤ 0.05) from the demographic composition of the regional population. Recreational anglers were predominantly White (≥ 60% of interviews) and Coloured (≥ 25%), while 84% of subsistence anglers were Coloured and 16% Black African. Most recreational anglers had permanent employment or were pensioners while <30% of subsistence anglers were permanently employed. Most recreational users (82%) accessed the lake with their own vehicle while subsistence anglers mainly walked (63%) or used a bicycle (28%). Recreational interviewees either consumed (59%), sold (11%), gave away (10%) or released (20%) some of their catch. Subsistence anglers either ate their catch (53%) and/or sold (41%) their catch. Within the subsistence sector no anglers released fish after capture or gave some of the catch away. We conclude that this inland fishery contributes to the livelihood of the rural poor who use the lake on a subsistence basis and that recreational-angler based tourism may contribute to increased income and employment opportunities through related service industries.
- Full Text:
- Date Issued: 2009
Why we should avoid the use of the term “Post-Abortion Syndrome” : commentary on Boulind and Edwards (2008)
- Authors: Macleod, Catriona I
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6277 , http://hdl.handle.net/10962/d1008277
- Description: Boulind and Edwards (2008) present a case study of Grace, a women suffering, in their words, from post-abortion syndrome (PAS). In this commentary I argue that while Boulind and Edwards’ (2008) report is useful in terms of documenting the therapeutic processes engaged in, they would have been better served in not hanging the distress experienced by Grace on the diagnostic category of post-abortion syndrome. Reasons for this are that: PAS is not a recognised category of diagnosis, despite having been initially proposed in 1981; applying a PTSD framework to abortion is questionable; PAS focuses attention on the abortion itself in isolation from the fact that abortion occurs in the context of severely problematic pregnancies and other important socio-cultural stressors; PAS, in the very manner in which it is formulated, invokes to a very complex politics of the foetus. Boulind and Edwards (2008) are careful in their documentation of the complexities of the case, and thus their use of PAS is unfortunate.
- Full Text:
- Date Issued: 2009
- Authors: Macleod, Catriona I
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6277 , http://hdl.handle.net/10962/d1008277
- Description: Boulind and Edwards (2008) present a case study of Grace, a women suffering, in their words, from post-abortion syndrome (PAS). In this commentary I argue that while Boulind and Edwards’ (2008) report is useful in terms of documenting the therapeutic processes engaged in, they would have been better served in not hanging the distress experienced by Grace on the diagnostic category of post-abortion syndrome. Reasons for this are that: PAS is not a recognised category of diagnosis, despite having been initially proposed in 1981; applying a PTSD framework to abortion is questionable; PAS focuses attention on the abortion itself in isolation from the fact that abortion occurs in the context of severely problematic pregnancies and other important socio-cultural stressors; PAS, in the very manner in which it is formulated, invokes to a very complex politics of the foetus. Boulind and Edwards (2008) are careful in their documentation of the complexities of the case, and thus their use of PAS is unfortunate.
- Full Text:
- Date Issued: 2009