The effect of the Xpert MTB/RIF test on the time to MDR-TB treatment initiation in a rural setting: a cohort study in South Africa’s Eastern Cape Province
- Iruedo, Joshua, O’Mahony , Don, Mabunda, Sikhumbuzo A, Wright, Graham, Cawe , Busisiwe
- Authors: Iruedo, Joshua , O’Mahony , Don , Mabunda, Sikhumbuzo A , Wright, Graham , Cawe , Busisiwe
- Date: 2017
- Subjects: South Africa Multidrug-resistant tuberculosis Computer File
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6098 , vital:45115 , https://DOI10.1186/s12879-017-2200-8
- Description: Background: There are significant delays in initiation of multidrug-resistant tuberculosis (MDR –TB) treatment. The Xpert MTB/RIF test has been shown to reduce the time to diagnosis and treatment of MDR-TB predominantly in urban centres. This study describes the time to treatment of MDR-TB and the effect of Xpert MTB/RIF on time to treatment in a deprived rural area in South Africa. Methods: This was a retrospective cohort study analysing the medical records of patients diagnosed with MDR-TB in King Sabata Dalindyebo Sub-District between 2009 and 2014. Numerical data were reported using the Kruskal-Wallis and Wilcoxon sum rank tests and categorical data compared using the two-sample test of proportions. Results: Of the 342 patients with MDR-TB identified, 285 were eligible for analysis, of whom 145 (61.4%) were HIV positive. The median time from sputum collection to MDR-TB diagnosis was 27 days (IQR: 2–45) and differed significantly between diagnostic modalities: Xpert MTB/RIF, 1 day (IQR: 1–4; n = 114: p less 0.0001); Line Probe Assay 12 days (IQR: 8–21; n = 28; p less 0.0001); and culture/phenotypic drug sensitivity testing 45 days (IQR: 39–59; n = 143: p less 0.0001). The time from diagnosis to treatment initiation was 14 days (IQR: 8–27) and did not differ significantly between diagnostic modality. The median time from sputum collection to treatment initiation was 49 days (IQR: 20–69) but differed significantly between diagnostic modalities: Xpert MTB/RIF, 18 days (IQR: 11–27; n = 114; p less 0.0001); Line Probe Assay 29 days (IQR: 14.5–53; n = 28; p les 0.0001); and culture/phenotypic drug sensitivity, 64 days (IQR: 50–103; n = 143: P less 0.0001). Age, sex and HIV status did not influence the time intervals. Conclusions: Xpert MTB/RIF significantly reduced the time to MDR-TB treatment in a deprived rural setting as a result of a reduced time to diagnosis. However, the national target of five days was not achieved. Further research is needed to explore and address programmatic and patient-related challenges contributing to delayed treatment initiation. Keywords: Xpert MTB/RIF, MDR-TB, Rural, Time-to-treatment, Cohort study
- Full Text:
- Date Issued: 2017
- Authors: Iruedo, Joshua , O’Mahony , Don , Mabunda, Sikhumbuzo A , Wright, Graham , Cawe , Busisiwe
- Date: 2017
- Subjects: South Africa Multidrug-resistant tuberculosis Computer File
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6098 , vital:45115 , https://DOI10.1186/s12879-017-2200-8
- Description: Background: There are significant delays in initiation of multidrug-resistant tuberculosis (MDR –TB) treatment. The Xpert MTB/RIF test has been shown to reduce the time to diagnosis and treatment of MDR-TB predominantly in urban centres. This study describes the time to treatment of MDR-TB and the effect of Xpert MTB/RIF on time to treatment in a deprived rural area in South Africa. Methods: This was a retrospective cohort study analysing the medical records of patients diagnosed with MDR-TB in King Sabata Dalindyebo Sub-District between 2009 and 2014. Numerical data were reported using the Kruskal-Wallis and Wilcoxon sum rank tests and categorical data compared using the two-sample test of proportions. Results: Of the 342 patients with MDR-TB identified, 285 were eligible for analysis, of whom 145 (61.4%) were HIV positive. The median time from sputum collection to MDR-TB diagnosis was 27 days (IQR: 2–45) and differed significantly between diagnostic modalities: Xpert MTB/RIF, 1 day (IQR: 1–4; n = 114: p less 0.0001); Line Probe Assay 12 days (IQR: 8–21; n = 28; p less 0.0001); and culture/phenotypic drug sensitivity testing 45 days (IQR: 39–59; n = 143: p less 0.0001). The time from diagnosis to treatment initiation was 14 days (IQR: 8–27) and did not differ significantly between diagnostic modality. The median time from sputum collection to treatment initiation was 49 days (IQR: 20–69) but differed significantly between diagnostic modalities: Xpert MTB/RIF, 18 days (IQR: 11–27; n = 114; p less 0.0001); Line Probe Assay 29 days (IQR: 14.5–53; n = 28; p les 0.0001); and culture/phenotypic drug sensitivity, 64 days (IQR: 50–103; n = 143: P less 0.0001). Age, sex and HIV status did not influence the time intervals. Conclusions: Xpert MTB/RIF significantly reduced the time to MDR-TB treatment in a deprived rural setting as a result of a reduced time to diagnosis. However, the national target of five days was not achieved. Further research is needed to explore and address programmatic and patient-related challenges contributing to delayed treatment initiation. Keywords: Xpert MTB/RIF, MDR-TB, Rural, Time-to-treatment, Cohort study
- Full Text:
- Date Issued: 2017
The FOXP2 forkhead domain binds to a variety of DNA sequences with different rates and affinities
- Webb, Helen, Steeb, Olga, Blane, Ashleigh, Rotherham, Lia, Aron, Shaun, Machanick, Philip, Dirr, Heinrich W, Fanucchi, Sylvia
- Authors: Webb, Helen , Steeb, Olga , Blane, Ashleigh , Rotherham, Lia , Aron, Shaun , Machanick, Philip , Dirr, Heinrich W , Fanucchi, Sylvia
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/439326 , vital:73567 , https://doi.org/10.1093/jb/mvx003
- Description: FOXP2 is a member of the P subfamily of FOX transcription factors, the DNA-binding domain of which is the winged helix forkhead domain (FHD). In this work we show that the FOXP2 FHD is able to bind to various DNA sequences, including a novel sequence identified in this work, with different affinities and rates as detected using surface plasmon resonance. Combining the experimental work with molecular docking, we show that high-affinity sequences remain bound to the protein for longer, form a greater number of interactions with the protein and induce a greater structural change in the protein than low-affinity sequences. We propose a binding model for the FOXP2 FHD that involves three types of binding sequence: low affinity sites which allow for rapid scanning of the genome by the protein in a partially unstructured state; moderate affinity sites which serve to locate the protein near target sites and high-affinity sites which secure the protein to the DNA and induce a conformational change necessary for functional binding and the possible initiation of downstream transcriptional events.
- Full Text:
- Date Issued: 2017
- Authors: Webb, Helen , Steeb, Olga , Blane, Ashleigh , Rotherham, Lia , Aron, Shaun , Machanick, Philip , Dirr, Heinrich W , Fanucchi, Sylvia
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/439326 , vital:73567 , https://doi.org/10.1093/jb/mvx003
- Description: FOXP2 is a member of the P subfamily of FOX transcription factors, the DNA-binding domain of which is the winged helix forkhead domain (FHD). In this work we show that the FOXP2 FHD is able to bind to various DNA sequences, including a novel sequence identified in this work, with different affinities and rates as detected using surface plasmon resonance. Combining the experimental work with molecular docking, we show that high-affinity sequences remain bound to the protein for longer, form a greater number of interactions with the protein and induce a greater structural change in the protein than low-affinity sequences. We propose a binding model for the FOXP2 FHD that involves three types of binding sequence: low affinity sites which allow for rapid scanning of the genome by the protein in a partially unstructured state; moderate affinity sites which serve to locate the protein near target sites and high-affinity sites which secure the protein to the DNA and induce a conformational change necessary for functional binding and the possible initiation of downstream transcriptional events.
- Full Text:
- Date Issued: 2017
The global distribution and diversity of protein vaccine candidate antigens in the highly virulent Streptococcus pnuemoniae serotype:
- Cornick, Jennifer E, Tastan Bishop, Özlem, Yalcin, Feyruz, Kiran, Anmol M, Kumwenda, Benjamin, Chaguza, Chrispin, Govindpershad, Shanil, Ousmane, Sani, Senghore, Madikay, du Plessis, Mignon, Pluschke, Gerd, 1952-, Ebruke, Chinelo, McGee, Lesley, Sigaùque , Beutel, Collard, Jean-Marc, Bentley, Stephen D, Kadioglu , Aras, Antonio, Martin, von Gottberg, Anne, French, Neil, Klugman, Keith P, Heyderman, Robert S, Alderson, Mark, Everett, Dean B
- Authors: Cornick, Jennifer E , Tastan Bishop, Özlem , Yalcin, Feyruz , Kiran, Anmol M , Kumwenda, Benjamin , Chaguza, Chrispin , Govindpershad, Shanil , Ousmane, Sani , Senghore, Madikay , du Plessis, Mignon , Pluschke, Gerd, 1952- , Ebruke, Chinelo , McGee, Lesley , Sigaùque , Beutel , Collard, Jean-Marc , Bentley, Stephen D , Kadioglu , Aras , Antonio, Martin , von Gottberg, Anne , French, Neil , Klugman, Keith P , Heyderman, Robert S , Alderson, Mark , Everett, Dean B
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148318 , vital:38729 , DOI: 10.1016/j.vaccine.2016.12.037
- Description: Serotype 1 is one of the most common causes of pneumococcal disease worldwide. Pneumococcal protein vaccines are currently being developed as an alternate intervention strategy to pneumococcal conjugate vaccines. Pre-requisites for an efficacious pneumococcal protein vaccine are universal presence and minimal variation of the target antigen in the pneumococcal population, and the capability to induce a robust human immune response. We used in silico analysis to assess the prevalence of seven protein vaccine candidates (CbpA, PcpA, PhtD, PspA, SP0148, SP1912, SP2108) among 445 serotype 1 pneumococci from 26 different countries, across four continents. CbpA (76%), PspA (68%), PhtD (28%), PcpA (11%) were not universally encoded in the study population, and would not provide full coverage against serotype 1.
- Full Text:
- Date Issued: 2017
- Authors: Cornick, Jennifer E , Tastan Bishop, Özlem , Yalcin, Feyruz , Kiran, Anmol M , Kumwenda, Benjamin , Chaguza, Chrispin , Govindpershad, Shanil , Ousmane, Sani , Senghore, Madikay , du Plessis, Mignon , Pluschke, Gerd, 1952- , Ebruke, Chinelo , McGee, Lesley , Sigaùque , Beutel , Collard, Jean-Marc , Bentley, Stephen D , Kadioglu , Aras , Antonio, Martin , von Gottberg, Anne , French, Neil , Klugman, Keith P , Heyderman, Robert S , Alderson, Mark , Everett, Dean B
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148318 , vital:38729 , DOI: 10.1016/j.vaccine.2016.12.037
- Description: Serotype 1 is one of the most common causes of pneumococcal disease worldwide. Pneumococcal protein vaccines are currently being developed as an alternate intervention strategy to pneumococcal conjugate vaccines. Pre-requisites for an efficacious pneumococcal protein vaccine are universal presence and minimal variation of the target antigen in the pneumococcal population, and the capability to induce a robust human immune response. We used in silico analysis to assess the prevalence of seven protein vaccine candidates (CbpA, PcpA, PhtD, PspA, SP0148, SP1912, SP2108) among 445 serotype 1 pneumococci from 26 different countries, across four continents. CbpA (76%), PspA (68%), PhtD (28%), PcpA (11%) were not universally encoded in the study population, and would not provide full coverage against serotype 1.
- Full Text:
- Date Issued: 2017
The influence of radiation-induced defects on thermoluminescence and optically stimulated luminescence of α-Al2O3: C
- Nyirenda, Angel N, Chithambo, Makaiko L
- Authors: Nyirenda, Angel N , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/119818 , vital:34786 , https://doi.org/10.1016/j.nimb.2017.02.077
- Description: It is known that when α-Al2O3:C is exposed to excessive amounts of ionising radiation, defects are induced within its matrix. We report the influence of radiation-induced defects on the thermoluminescence (TL) and optically stimulated luminescence (OSL) measured from α-Al2O3:C after irradiation to 1000 Gy. These radiation-induced defects are thermally unstable in the region 450–650 °C and result in TL peaks in this range when the TL is measured at 1 °C/s. Heating a sample to 700 °C obliterates the radiation-induced defects, that is, the TL peaks corresponding to the radiation induced defects are no longer observed in the subsequent TL measurements when moderate irradiation doses below 10 Gy are used. The charge traps associated with these radiation-induced defects are more stable than the dosimetric trap when the sample is exposed to either sunlight or 470-nm blue light from LEDs. TL glow curves measured following the defect-inducing irradiation produce a dosimetric peak that is broader and positioned at a higher temperature than observed in glow curves obtained before the heavy irradiation. In addition, sample sensitization/desensitization occurs due to the presence of these radiation-induced defects. Furthermore, both the activation energy and the kinetic order of the dosimetric peak evaluated when the radiation-induced defects are present in the sample are significantly lower in value than those obtained when these defects are absent. The radiation-induced defects also affect the shape and total light sum of the OSL signal as well as the position and width of the resultant residual phototransferred thermoluminescence main peak.
- Full Text: false
- Date Issued: 2017
- Authors: Nyirenda, Angel N , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/119818 , vital:34786 , https://doi.org/10.1016/j.nimb.2017.02.077
- Description: It is known that when α-Al2O3:C is exposed to excessive amounts of ionising radiation, defects are induced within its matrix. We report the influence of radiation-induced defects on the thermoluminescence (TL) and optically stimulated luminescence (OSL) measured from α-Al2O3:C after irradiation to 1000 Gy. These radiation-induced defects are thermally unstable in the region 450–650 °C and result in TL peaks in this range when the TL is measured at 1 °C/s. Heating a sample to 700 °C obliterates the radiation-induced defects, that is, the TL peaks corresponding to the radiation induced defects are no longer observed in the subsequent TL measurements when moderate irradiation doses below 10 Gy are used. The charge traps associated with these radiation-induced defects are more stable than the dosimetric trap when the sample is exposed to either sunlight or 470-nm blue light from LEDs. TL glow curves measured following the defect-inducing irradiation produce a dosimetric peak that is broader and positioned at a higher temperature than observed in glow curves obtained before the heavy irradiation. In addition, sample sensitization/desensitization occurs due to the presence of these radiation-induced defects. Furthermore, both the activation energy and the kinetic order of the dosimetric peak evaluated when the radiation-induced defects are present in the sample are significantly lower in value than those obtained when these defects are absent. The radiation-induced defects also affect the shape and total light sum of the OSL signal as well as the position and width of the resultant residual phototransferred thermoluminescence main peak.
- Full Text: false
- Date Issued: 2017
Thinking with Shakespeare: The Merchant of Venice, Shylock, Caliban and the dynamics of social scale
- Authors: Wright, Laurence
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/454007 , vital:75304 , 10.4314/sisa.v29i1.3
- Description: Contemporary criticism seldom acknowledges Shakespeare’s sensitivity to longer-term historical trajectories. One such variable is social scale. If dramatic conflict in The Merchant of Venice is interpreted solely in terms of clashes between ethical character, social allegiance, and religious affiliation, at the end of the play these clashes persist as a morass of irreconcilables, unresolved and irresolvable. The audience is left in unconditioned liberty to make up its own mind. This paper argues that changing social scale provides a framework which allows the ethical dilemmas posed by The Merchant of Venice to be interpreted coherently, bringing us closer to the experience of ‘thinking with Shakespeare’. Shakespeare’s drama anticipates the rise of large-scale cosmopolitan society and, without underestimating the social tensions involved, challenges the audience to welcome an unknown new world appearing over the horizon.
- Full Text:
- Date Issued: 2017
Thinking with Shakespeare: The Merchant of Venice, Shylock, Caliban and the dynamics of social scale
- Authors: Wright, Laurence
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/454007 , vital:75304 , 10.4314/sisa.v29i1.3
- Description: Contemporary criticism seldom acknowledges Shakespeare’s sensitivity to longer-term historical trajectories. One such variable is social scale. If dramatic conflict in The Merchant of Venice is interpreted solely in terms of clashes between ethical character, social allegiance, and religious affiliation, at the end of the play these clashes persist as a morass of irreconcilables, unresolved and irresolvable. The audience is left in unconditioned liberty to make up its own mind. This paper argues that changing social scale provides a framework which allows the ethical dilemmas posed by The Merchant of Venice to be interpreted coherently, bringing us closer to the experience of ‘thinking with Shakespeare’. Shakespeare’s drama anticipates the rise of large-scale cosmopolitan society and, without underestimating the social tensions involved, challenges the audience to welcome an unknown new world appearing over the horizon.
- Full Text:
- Date Issued: 2017
Wheelchair users, access and exclusion in South Africa higher education
- Chiwandire, Desire, Vincent, Louise
- Authors: Chiwandire, Desire , Vincent, Louise
- Date: 2017
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59984 , vital:27717 , doi: 10.4102/ajod.v6i0.353
- Description: Background: South Africa’s Constitution guarantees everyone, including persons with disabilities, the right to education. A variety of laws are in place obliging higher education institutions to provide appropriate physical access to education sites for all. In practice, however, many buildings remain inaccessible to people with physical disabilities. Objectives: To describe what measures South African universities are taking to make their built environments more accessible to students with diverse types of disabilities, and to assess the adequacy of such measures. Method: We conducted semi-structured in-depth face-to-face interviews with disability unit staff members (DUSMs) based at 10 different public universities in South Africa. Results: Challenges with promoting higher education accessibility for wheelchair users include the preservation and heritage justification for failing to modify older buildings, ad hoc approaches to creating accessible environments and failure to address access to toilets, libraries and transport facilities for wheelchair users. Conclusion: South African universities are still not places where all students are equally able to integrate socially. DUSMs know what ought to be done to make campuses more accessible and welcoming to students with disabilities and should be empowered to play a leading role in sensitising non-disabled members of universities, to create greater awareness of, and appreciation for, the multiple ways in which wheelchair user students continue to be excluded from full participation in university life. South African universities need to adopt a systemic approach to inclusion, which fosters an understanding of inclusion as a fundamental right rather than as a luxury.
- Full Text:
- Date Issued: 2017
- Authors: Chiwandire, Desire , Vincent, Louise
- Date: 2017
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59984 , vital:27717 , doi: 10.4102/ajod.v6i0.353
- Description: Background: South Africa’s Constitution guarantees everyone, including persons with disabilities, the right to education. A variety of laws are in place obliging higher education institutions to provide appropriate physical access to education sites for all. In practice, however, many buildings remain inaccessible to people with physical disabilities. Objectives: To describe what measures South African universities are taking to make their built environments more accessible to students with diverse types of disabilities, and to assess the adequacy of such measures. Method: We conducted semi-structured in-depth face-to-face interviews with disability unit staff members (DUSMs) based at 10 different public universities in South Africa. Results: Challenges with promoting higher education accessibility for wheelchair users include the preservation and heritage justification for failing to modify older buildings, ad hoc approaches to creating accessible environments and failure to address access to toilets, libraries and transport facilities for wheelchair users. Conclusion: South African universities are still not places where all students are equally able to integrate socially. DUSMs know what ought to be done to make campuses more accessible and welcoming to students with disabilities and should be empowered to play a leading role in sensitising non-disabled members of universities, to create greater awareness of, and appreciation for, the multiple ways in which wheelchair user students continue to be excluded from full participation in university life. South African universities need to adopt a systemic approach to inclusion, which fosters an understanding of inclusion as a fundamental right rather than as a luxury.
- Full Text:
- Date Issued: 2017
Academic literacy and the decontextualised learner
- Boughey, Chrissie, McKenna, Sioux
- Authors: Boughey, Chrissie , McKenna, Sioux
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/64651 , vital:28585 , http://www.DOI:10.14426/cristal.v4i2.80
- Description: The literacy practices that are valued in the university emerge from specific disciplinary histories yet students are often expected to master these as if they were common sense and natural. This article argues that the autonomous model of literacy, which sees language use as the application of a set of neutral skills, continues to dominate in South African universities. This model denies the extent to which taking on disciplinary literacy practices can be difficult and have implications for identity. It also allows disciplinary norms to remain largely opaque and beyond critique. Furthermore, the autonomous model of literacy is often coupled with a discourse of the ‘decontextualised learner’ who is divorced from her social context, with higher education success seen to be resting largely upon attributes inherent in, or lacking from, the individual. Sadly, alternative critical social understandings have not been widely taken up despite their being well researched. Indeed, such understandings have often been misappropriated in ways that draw on critical social terminology to offer autonomous, decontextualised, remedial student interventions. We argue that these issues are implicated in students’ accusations that universities are alienating spaces.
- Full Text:
- Date Issued: 2016
- Authors: Boughey, Chrissie , McKenna, Sioux
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/64651 , vital:28585 , http://www.DOI:10.14426/cristal.v4i2.80
- Description: The literacy practices that are valued in the university emerge from specific disciplinary histories yet students are often expected to master these as if they were common sense and natural. This article argues that the autonomous model of literacy, which sees language use as the application of a set of neutral skills, continues to dominate in South African universities. This model denies the extent to which taking on disciplinary literacy practices can be difficult and have implications for identity. It also allows disciplinary norms to remain largely opaque and beyond critique. Furthermore, the autonomous model of literacy is often coupled with a discourse of the ‘decontextualised learner’ who is divorced from her social context, with higher education success seen to be resting largely upon attributes inherent in, or lacking from, the individual. Sadly, alternative critical social understandings have not been widely taken up despite their being well researched. Indeed, such understandings have often been misappropriated in ways that draw on critical social terminology to offer autonomous, decontextualised, remedial student interventions. We argue that these issues are implicated in students’ accusations that universities are alienating spaces.
- Full Text:
- Date Issued: 2016
Detection of plant growth enhancing features in psychrotolerant yeasts from Patagonia (Argentina)
- Mestre, María C, Fontenla, Sonia, Bruzone, Marie C, Fernández, Natalia V, Dames, Joanna F
- Authors: Mestre, María C , Fontenla, Sonia , Bruzone, Marie C , Fernández, Natalia V , Dames, Joanna F
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448581 , vital:74744 , https://doi.org/10.1002/jobm.201500728
- Description: This study explores the biotechnological potential for plant production of twelve psychrotolerant yeasts strains from Northwest‐Patagonia. These strains were isolated from different substrates associated with Nothofagus sp. in native forests and Vaccinium sp. in a commercial plantation. Yeasts characterization was performed using in vitro assays to evaluate the production of auxin‐like compounds and siderophores, ability to solubilize inorganic phosphate and to reduce common plant pathogen growth. Strain YF8.3 identified as Aureobasidium pullullans was the main producer of auxin‐like and siderophores compounds. Phosphate solubilization was a characteristic observed by strains L8.12 and CRUB1775 identified as Holtermaniella takashimae and Candida maritima, respectively. Different yeast strains were able to inhibit the growth of Verticillium dahliae PPRI5569 and Pythium aphanidermatum PPRI 9009, but they all failed to inhibit the growth of Fusarium oxysporum PPRI5457. The present study, suggests that yeasts present in different environments in Northwestern‐Patagonian have physiological in vitro features which may influence plant growth. These results are promising for the developing of biological products based on Patagonian yeasts for plant production in cold‐temperate regions.
- Full Text:
- Date Issued: 2016
- Authors: Mestre, María C , Fontenla, Sonia , Bruzone, Marie C , Fernández, Natalia V , Dames, Joanna F
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448581 , vital:74744 , https://doi.org/10.1002/jobm.201500728
- Description: This study explores the biotechnological potential for plant production of twelve psychrotolerant yeasts strains from Northwest‐Patagonia. These strains were isolated from different substrates associated with Nothofagus sp. in native forests and Vaccinium sp. in a commercial plantation. Yeasts characterization was performed using in vitro assays to evaluate the production of auxin‐like compounds and siderophores, ability to solubilize inorganic phosphate and to reduce common plant pathogen growth. Strain YF8.3 identified as Aureobasidium pullullans was the main producer of auxin‐like and siderophores compounds. Phosphate solubilization was a characteristic observed by strains L8.12 and CRUB1775 identified as Holtermaniella takashimae and Candida maritima, respectively. Different yeast strains were able to inhibit the growth of Verticillium dahliae PPRI5569 and Pythium aphanidermatum PPRI 9009, but they all failed to inhibit the growth of Fusarium oxysporum PPRI5457. The present study, suggests that yeasts present in different environments in Northwestern‐Patagonian have physiological in vitro features which may influence plant growth. These results are promising for the developing of biological products based on Patagonian yeasts for plant production in cold‐temperate regions.
- Full Text:
- Date Issued: 2016
Diatom-based water quality monitoring in southern Africa: challenges and future prospects
- Dalu, Tatenda, Froneman, P William
- Authors: Dalu, Tatenda , Froneman, P William
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124297 , vital:35590 , http://dx.doi.org/10.4314/wsa.v42i4.05
- Description: Diatoms are of significant ecological importance in aquatic ecosystems, which stems from their dynamic position at the base of the trophic web as primary producers. Because diatom communities have specific environmental requirements and respond rapidly to changes in environmental conditions they are often employed as a cost-effective method to assess anthropogenic impacts and health statuses of aquatic ecosystems, particularly in Europe and North America. The purpose of this review is to summarise the challenges and future prospects associated with biological water quality monitoring using diatoms with special focus on southern Africa. Much work still needs to be carried out on diatom tolerances, ecological preferences and ecophysiology. It is recommended that past research pertaining to African diatom taxonomy should be made readily accessible to all through electronic media for use as a reference point. Moreover, following the same approach as for macroinvertebrate biomonitoring, African and other developing countries can resort to intermediate diatom taxonomy (i.e. genus), which is easier, less time-consuming and requires less-skilled personnel. While the lack of capacity and baseline information on diatom community composition and ecological requirements represent significant hurdles, diatom biomonitoring potentially holds much promise for understanding the ecological functioning and management of aquatic ecosystems in southern Africa. The application of diatom-based water quality assessment protocols has direct and immediate value for use as an ‘added-value’ assessment tool in addition to the use of macroinvertebrates and fish indices as these can indicate anthropogenically impacted and pristine sites.
- Full Text:
- Date Issued: 2016
- Authors: Dalu, Tatenda , Froneman, P William
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124297 , vital:35590 , http://dx.doi.org/10.4314/wsa.v42i4.05
- Description: Diatoms are of significant ecological importance in aquatic ecosystems, which stems from their dynamic position at the base of the trophic web as primary producers. Because diatom communities have specific environmental requirements and respond rapidly to changes in environmental conditions they are often employed as a cost-effective method to assess anthropogenic impacts and health statuses of aquatic ecosystems, particularly in Europe and North America. The purpose of this review is to summarise the challenges and future prospects associated with biological water quality monitoring using diatoms with special focus on southern Africa. Much work still needs to be carried out on diatom tolerances, ecological preferences and ecophysiology. It is recommended that past research pertaining to African diatom taxonomy should be made readily accessible to all through electronic media for use as a reference point. Moreover, following the same approach as for macroinvertebrate biomonitoring, African and other developing countries can resort to intermediate diatom taxonomy (i.e. genus), which is easier, less time-consuming and requires less-skilled personnel. While the lack of capacity and baseline information on diatom community composition and ecological requirements represent significant hurdles, diatom biomonitoring potentially holds much promise for understanding the ecological functioning and management of aquatic ecosystems in southern Africa. The application of diatom-based water quality assessment protocols has direct and immediate value for use as an ‘added-value’ assessment tool in addition to the use of macroinvertebrates and fish indices as these can indicate anthropogenically impacted and pristine sites.
- Full Text:
- Date Issued: 2016
Do indigenous street trees promote more biodiversity than alien ones? evidence using mistletoes and birds in South Africa
- Authors: Shackleton, Charlie M
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/64663 , vital:28587 , http://www.doi:10.3390/f7070134
- Description: Trees in urban landscapes provide a range of ecosystem services, including habitat, refugia,food, and corridors for other fauna and flora. However, there is some debate whether the richness and abundance of other biodiversity supported is influenced by the provenance of trees, i.e., native or non-native. This study assessed the presence of mistletoes and birds (and nests) in 1261 street trees. There were marked differences between native and non-native street trees, with the former having a significantly higher prevalence of birds (and nests) and supporting more species and in greater densities, whilst the latter supported a higher prevalence of mistletoes. Additionally, for birds, the proximity to green space, tree size and species were also important, whilst for mistletoes, the proximity to green space, slope aspect, and tree species were significant. Preference ratios indicated that some tree species had a higher than random occurrence of birds or mistletoes, whilst others had a low abundance. The indigenous tree species, Acacia karroo Hayne was the only reasonably abundant street tree species that was important for birds, nests, and mistletoes. At the street scale, there was a positive relationship between street tree species richness and bird species richness. These results emphasise the importance of selecting appropriate tree species if biodiversity conservation is a core outcome.
- Full Text:
- Date Issued: 2016
- Authors: Shackleton, Charlie M
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/64663 , vital:28587 , http://www.doi:10.3390/f7070134
- Description: Trees in urban landscapes provide a range of ecosystem services, including habitat, refugia,food, and corridors for other fauna and flora. However, there is some debate whether the richness and abundance of other biodiversity supported is influenced by the provenance of trees, i.e., native or non-native. This study assessed the presence of mistletoes and birds (and nests) in 1261 street trees. There were marked differences between native and non-native street trees, with the former having a significantly higher prevalence of birds (and nests) and supporting more species and in greater densities, whilst the latter supported a higher prevalence of mistletoes. Additionally, for birds, the proximity to green space, tree size and species were also important, whilst for mistletoes, the proximity to green space, slope aspect, and tree species were significant. Preference ratios indicated that some tree species had a higher than random occurrence of birds or mistletoes, whilst others had a low abundance. The indigenous tree species, Acacia karroo Hayne was the only reasonably abundant street tree species that was important for birds, nests, and mistletoes. At the street scale, there was a positive relationship between street tree species richness and bird species richness. These results emphasise the importance of selecting appropriate tree species if biodiversity conservation is a core outcome.
- Full Text:
- Date Issued: 2016
Docking of HIV protease to silver nanoparticles
- Whiteley, Chris G, Shing, C-Y, Kuo, C-C, Lee, Duu-Jong
- Authors: Whiteley, Chris G , Shing, C-Y , Kuo, C-C , Lee, Duu-Jong
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67105 , vital:29032 , https://doi.org/10.1016/j.jtice.2015.10.029
- Description: publisher version , This interaction of silver nanoparticles (AgNP) with human immune-deficiency virus aspartic protease (HIVPR) is examined by molecular dynamics simulation using the Colores (Situs) package and biophysical techniques using UV–vis spectroscopy, dynamic light scattering, transmission electron microscopy and circular dichroism. The ‘docking’ of AgNP with HIVPR creates a complex [AgNP–HIVPR] to initiate a hypochromic time-dependent red-shift for the surface plasmon resonance maximum. MD simulations reflect large perturbations to enzyme conformations by fluctuations of both rmsd and B-factors. Increase in changes to electrostatic potentials within the enzyme, especially, with chain B, suggest hydrophobic interactions for the binding of the AgNP. This is supported by changes to mainchain and sidechain dihedrals for many hydrophobic amino acid including Cys95, Trp6 and Trp42. Circular dichroism spectra reveal disappearance of α-helices and β-sheets and increase in random coil first from chain B then chain A. During initial stages of the interactive simulation the enzyme is conformational flexible to accommodate the AgNP, that docks with the enzyme under a cooperative mechanism, until a more stable structure is formed at convergence. There is a decrease in size of the HIVPR–AgNP complex measured by changes to the gyration radius supporting evidence that the AgNP associates, initially, with chain B.
- Full Text: false
- Date Issued: 2016
- Authors: Whiteley, Chris G , Shing, C-Y , Kuo, C-C , Lee, Duu-Jong
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67105 , vital:29032 , https://doi.org/10.1016/j.jtice.2015.10.029
- Description: publisher version , This interaction of silver nanoparticles (AgNP) with human immune-deficiency virus aspartic protease (HIVPR) is examined by molecular dynamics simulation using the Colores (Situs) package and biophysical techniques using UV–vis spectroscopy, dynamic light scattering, transmission electron microscopy and circular dichroism. The ‘docking’ of AgNP with HIVPR creates a complex [AgNP–HIVPR] to initiate a hypochromic time-dependent red-shift for the surface plasmon resonance maximum. MD simulations reflect large perturbations to enzyme conformations by fluctuations of both rmsd and B-factors. Increase in changes to electrostatic potentials within the enzyme, especially, with chain B, suggest hydrophobic interactions for the binding of the AgNP. This is supported by changes to mainchain and sidechain dihedrals for many hydrophobic amino acid including Cys95, Trp6 and Trp42. Circular dichroism spectra reveal disappearance of α-helices and β-sheets and increase in random coil first from chain B then chain A. During initial stages of the interactive simulation the enzyme is conformational flexible to accommodate the AgNP, that docks with the enzyme under a cooperative mechanism, until a more stable structure is formed at convergence. There is a decrease in size of the HIVPR–AgNP complex measured by changes to the gyration radius supporting evidence that the AgNP associates, initially, with chain B.
- Full Text: false
- Date Issued: 2016
Encouraging pro-environmental behaviour: energy use and recycling at Rhodes University, South Africa
- Mtutu, Paidamoyo, Thondhlana, Gladman
- Authors: Mtutu, Paidamoyo , Thondhlana, Gladman
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67743 , vital:29136 , https://doi.org/10.1016/j.habitatint.2015.11.031
- Description: Publisher version , The rapid expansion of student numbers, staff and support infrastructures in higher education institutions often result in increased demand for resources such as energy and paper. Promoting pro-environmental behaviour is critical if higher education institutions are to achieve sustainable resource use. Using surveys, reported energy use and recycling behaviour of staff and students in the Faculty of Education at Rhodes University, South Africa was explored. The results showed that self-reported pro-environmental behaviour was mediated by demographic factors and personal values such as ‘liking of aesthetic beauty and biodiversity’, ‘social relations’, ‘a varied life’ and ‘freedom’. Personal values, though key in shaping participants' attitudes toward the environment did not always translate into pro-environmental behaviour. Situational factors beyond the control of participants were cited as barriers to pro-environmental actions. Lessons from this study point to the need to carefully study the assumptions underlying intervention strategies aimed at promoting pro-environmental behaviour and to get rid of barriers to enable pro-environmental actions.
- Full Text: false
- Date Issued: 2016
Encouraging pro-environmental behaviour: energy use and recycling at Rhodes University, South Africa
- Authors: Mtutu, Paidamoyo , Thondhlana, Gladman
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67743 , vital:29136 , https://doi.org/10.1016/j.habitatint.2015.11.031
- Description: Publisher version , The rapid expansion of student numbers, staff and support infrastructures in higher education institutions often result in increased demand for resources such as energy and paper. Promoting pro-environmental behaviour is critical if higher education institutions are to achieve sustainable resource use. Using surveys, reported energy use and recycling behaviour of staff and students in the Faculty of Education at Rhodes University, South Africa was explored. The results showed that self-reported pro-environmental behaviour was mediated by demographic factors and personal values such as ‘liking of aesthetic beauty and biodiversity’, ‘social relations’, ‘a varied life’ and ‘freedom’. Personal values, though key in shaping participants' attitudes toward the environment did not always translate into pro-environmental behaviour. Situational factors beyond the control of participants were cited as barriers to pro-environmental actions. Lessons from this study point to the need to carefully study the assumptions underlying intervention strategies aimed at promoting pro-environmental behaviour and to get rid of barriers to enable pro-environmental actions.
- Full Text: false
- Date Issued: 2016
Reimagining curriculum through a Bernsteinian lens: rethinking the canon in Political Science
- Authors: Clarence, Sherran
- Date: 2016
- Language: English
- Type: text , conference publication
- Identifier: http://hdl.handle.net/10962/66961 , vital:29006
- Full Text:
- Date Issued: 2016
- Authors: Clarence, Sherran
- Date: 2016
- Language: English
- Type: text , conference publication
- Identifier: http://hdl.handle.net/10962/66961 , vital:29006
- Full Text:
- Date Issued: 2016
TeleWeaver: an architectural overview of a customised application server for rurality
- Tsietsi, Mosiuoa, Terzoli, Alfredo, Gumbo, Sibukelo
- Authors: Tsietsi, Mosiuoa , Terzoli, Alfredo , Gumbo, Sibukelo
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430624 , vital:72704 , 10.1109/ISTAFRICA.2016.7530616
- Description: The Siyakhula Living Lab in the rural Eastern Cape province of South Africa has been in existence for over a decade now. In this time, sever-al software artefacts have been developed by students and partners with the aim of providing contextually-relevant services to the rural community. However, reliance on different platforms and paradigms has meant that the deployment of such services would be difficult to implement and maintain reliably in actual practice. What is required is a single software platform that can act as a docking station for multiple applications, as well as a routing substrate for applications living inside and outside the platform. A candidate platform to enable this is currently being integrated under the codename Teleweaver and is built from a free, open source J2EE application server and integrates with other software components. This paper provides an architectural overview of the platform and demonstrates how it provides a sustainable context for application development going forward.
- Full Text:
- Date Issued: 2016
- Authors: Tsietsi, Mosiuoa , Terzoli, Alfredo , Gumbo, Sibukelo
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430624 , vital:72704 , 10.1109/ISTAFRICA.2016.7530616
- Description: The Siyakhula Living Lab in the rural Eastern Cape province of South Africa has been in existence for over a decade now. In this time, sever-al software artefacts have been developed by students and partners with the aim of providing contextually-relevant services to the rural community. However, reliance on different platforms and paradigms has meant that the deployment of such services would be difficult to implement and maintain reliably in actual practice. What is required is a single software platform that can act as a docking station for multiple applications, as well as a routing substrate for applications living inside and outside the platform. A candidate platform to enable this is currently being integrated under the codename Teleweaver and is built from a free, open source J2EE application server and integrates with other software components. This paper provides an architectural overview of the platform and demonstrates how it provides a sustainable context for application development going forward.
- Full Text:
- Date Issued: 2016
The inhibitory effects of various substrate pre-treatment by-products and wash liquors on mannanolytic enzymes
- Malgas, Samkelo, Van Dyk, J Susan, Abboo, Sagaran, Pletschke, Brett I
- Authors: Malgas, Samkelo , Van Dyk, J Susan , Abboo, Sagaran , Pletschke, Brett I
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66156 , vital:28911 , https://doi.org/10.1016/j.molcatb.2015.11.014
- Description: publisher version , Biomass pre-treatment is essential for achieving high levels of bioconversion through increased accessibility of hydrolytic enzymes to hydrolysable carbohydrates. However, pre-treatment by-products, such as sugar and lignin degradation products, can negatively affect the performance of hydrolytic (mannanolytic) enzymes. In this study, two monomeric sugars, five sugar degradation products, five lignin derivatives and four liquors from biomass feedstocks pre-treated by different technologies, were evaluated for their inhibitory effects on mannanolytic enzymes (α-galactosidases, β-mannanases and β-mannosidases). Lignin derivatives elicited the greatest inhibitory effect on the mannanolytic enzymes, followed by organic acids and furan derivatives derived from sugar degradation. Lignin derivative inhibition appeared to be as a result of protein–phenolic complexation, leading to protein precipitating out of solution. The functional groups on the phenolic lignin derivatives appeared to be directly related to the ability of the phenolic to interfere with enzyme activity, with the phenolic containing the highest hydroxyl group content exhibiting the greatest inhibition. It was also demonstrated that various pre-treatment technologies render different pre-treatment soluble by-products which interact in various ways with the mannanolytic enzymes. The different types of biomass (i.e. different plant species) were also shown to release different by-products that interacted with the mannanolytic enzymes in a diverse manner even when the biomass was pre-treated using the same technology. Enzyme inhibition by pre-treatment by-products can be alleviated through the removal of these compounds prior to enzymatic hydrolysis to maximize enzyme activity.
- Full Text: false
- Date Issued: 2016
- Authors: Malgas, Samkelo , Van Dyk, J Susan , Abboo, Sagaran , Pletschke, Brett I
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66156 , vital:28911 , https://doi.org/10.1016/j.molcatb.2015.11.014
- Description: publisher version , Biomass pre-treatment is essential for achieving high levels of bioconversion through increased accessibility of hydrolytic enzymes to hydrolysable carbohydrates. However, pre-treatment by-products, such as sugar and lignin degradation products, can negatively affect the performance of hydrolytic (mannanolytic) enzymes. In this study, two monomeric sugars, five sugar degradation products, five lignin derivatives and four liquors from biomass feedstocks pre-treated by different technologies, were evaluated for their inhibitory effects on mannanolytic enzymes (α-galactosidases, β-mannanases and β-mannosidases). Lignin derivatives elicited the greatest inhibitory effect on the mannanolytic enzymes, followed by organic acids and furan derivatives derived from sugar degradation. Lignin derivative inhibition appeared to be as a result of protein–phenolic complexation, leading to protein precipitating out of solution. The functional groups on the phenolic lignin derivatives appeared to be directly related to the ability of the phenolic to interfere with enzyme activity, with the phenolic containing the highest hydroxyl group content exhibiting the greatest inhibition. It was also demonstrated that various pre-treatment technologies render different pre-treatment soluble by-products which interact in various ways with the mannanolytic enzymes. The different types of biomass (i.e. different plant species) were also shown to release different by-products that interacted with the mannanolytic enzymes in a diverse manner even when the biomass was pre-treated using the same technology. Enzyme inhibition by pre-treatment by-products can be alleviated through the removal of these compounds prior to enzymatic hydrolysis to maximize enzyme activity.
- Full Text: false
- Date Issued: 2016
Vertebrate Biostratigraphy of the Witteberg Group and the Devonian-Carboniferous boundary in South Africa
- Authors: Gess, Robert W
- Date: 2016
- Language: English
- Type: text , boook chapter
- Identifier: http://hdl.handle.net/10962/73987 , vital:30248 , https://doi.org/10.1007/978-3-319-40859-0_13
- Description: Witteberg Group rocks are Late Devonian to Early Carboniferous in age. Comparison with Laurasian sea-level curves has correlated the earliest Carboniferous Tournasian transgression, with the argillaceous Kweekvlei Formation, overlying the arenaceous Witpoort Formation. The Devonian/Carboniferous boundary is globally characterised by a Mass Extinction which extinguished the entire grade of placoderm fish and radically reduced sarcopterygian and acanthodian diversity, preluding an Early Carboniferous radiation of actinopterygians. Analysis of Cape Supergroup biostratigraphy reveals that a fauna preservationally dominated by placoderms, sharks, and gyracanthid acanthodians may be traced from the Upper Bokkeveld Group through the Wagondrift Formation (Witteberg Group) to the Witpoort Formation, wherein it displays an increased diversity of placoderms, as well as sarcopterygians. Overlying strata contain no placoderms or sarcopterygians, but present are some relict sharks and acanthodians, and an increasing abundance of actinopterygians. This congruence confirms sea-level curve based age estimates of the Witteberg Group and the position of the Devonian/Carboniferous boundary.
- Full Text: false
- Date Issued: 2016
- Authors: Gess, Robert W
- Date: 2016
- Language: English
- Type: text , boook chapter
- Identifier: http://hdl.handle.net/10962/73987 , vital:30248 , https://doi.org/10.1007/978-3-319-40859-0_13
- Description: Witteberg Group rocks are Late Devonian to Early Carboniferous in age. Comparison with Laurasian sea-level curves has correlated the earliest Carboniferous Tournasian transgression, with the argillaceous Kweekvlei Formation, overlying the arenaceous Witpoort Formation. The Devonian/Carboniferous boundary is globally characterised by a Mass Extinction which extinguished the entire grade of placoderm fish and radically reduced sarcopterygian and acanthodian diversity, preluding an Early Carboniferous radiation of actinopterygians. Analysis of Cape Supergroup biostratigraphy reveals that a fauna preservationally dominated by placoderms, sharks, and gyracanthid acanthodians may be traced from the Upper Bokkeveld Group through the Wagondrift Formation (Witteberg Group) to the Witpoort Formation, wherein it displays an increased diversity of placoderms, as well as sarcopterygians. Overlying strata contain no placoderms or sarcopterygians, but present are some relict sharks and acanthodians, and an increasing abundance of actinopterygians. This congruence confirms sea-level curve based age estimates of the Witteberg Group and the position of the Devonian/Carboniferous boundary.
- Full Text: false
- Date Issued: 2016
A Comparison of Four End-User Devices as Thin Clients for Public Access to the Internet in Poor Communities
- Duff, Kevin, Siebörger, Ingrid, Terzoli, Alfredo
- Authors: Duff, Kevin , Siebörger, Ingrid , Terzoli, Alfredo
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430892 , vital:72725 , https://doi.org/10.1007/978-3-319-16886-9_24
- Description: In poor areas, where ICT infrastructure is being deployed with devel-opmental aims, there is a need to provide appropriate, sustainable technologies that meet the needs of the local community. Current trends for ICT interventions favour the use of mobile user equipment, such as tablets and cellphones, but we think that they are inappropriate to allow production as opposed to mainly consumption of digital con-tent, at least for the foreseeable future. Thus our objective is to reduce the cost of deployment of traditional communal Internet Access Points using PCs. In this paper we compare four candidate computers to be used as thin clients in such settings, according to seven different cate-gories. Our study identifies the strengths, weaknesses and problems of each device, and concludes with recommendations for anybody wish-ing to deploy such devices as Linux Terminal Server Project (LTSP) thin clients in a public Internet Access Point.
- Full Text:
- Date Issued: 2015
- Authors: Duff, Kevin , Siebörger, Ingrid , Terzoli, Alfredo
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430892 , vital:72725 , https://doi.org/10.1007/978-3-319-16886-9_24
- Description: In poor areas, where ICT infrastructure is being deployed with devel-opmental aims, there is a need to provide appropriate, sustainable technologies that meet the needs of the local community. Current trends for ICT interventions favour the use of mobile user equipment, such as tablets and cellphones, but we think that they are inappropriate to allow production as opposed to mainly consumption of digital con-tent, at least for the foreseeable future. Thus our objective is to reduce the cost of deployment of traditional communal Internet Access Points using PCs. In this paper we compare four candidate computers to be used as thin clients in such settings, according to seven different cate-gories. Our study identifies the strengths, weaknesses and problems of each device, and concludes with recommendations for anybody wish-ing to deploy such devices as Linux Terminal Server Project (LTSP) thin clients in a public Internet Access Point.
- Full Text:
- Date Issued: 2015
Aspects of the biology and life history of largespot pompano, Trachinotus botla, in South Africa
- Parker, Daniel M, Booth, Anthony J
- Authors: Parker, Daniel M , Booth, Anthony J
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123798 , vital:35499 , https://doi.10.1071/MF14029
- Description: Trachinotus botla is an important recreational surf zone-dependent fish species distributed in the Indo-west Pacific from South Africa to Australia. In South Africa it is restricted to the northern KwaZulu-Natal coast. Biological investigations revealed that it is a fast growing species that attains a maximum age of, 7 years. Males and females sexually matured in their third year. It has a protracted summer spawning season with evidence of serial spawning behaviour. T. botla is an opportunistic predator with a generalist diet, with fish feeding on a wide variety of prey items particularly those that are temporally ‘superabundant’. Small fish fed predominantly on copepods and terrestrial insects, whereas larger fish consumed bivalves and crabs. Teleosts, primarily engraulids, were important components to the diet of fish of all sizes. An ontogenetic dietary shift was observed just after sexual maturity (300-mm fork length) that is possibly linked to a change in habitat preference with larger fish foraging on deeper reefs.
- Full Text:
- Date Issued: 2015
- Authors: Parker, Daniel M , Booth, Anthony J
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123798 , vital:35499 , https://doi.10.1071/MF14029
- Description: Trachinotus botla is an important recreational surf zone-dependent fish species distributed in the Indo-west Pacific from South Africa to Australia. In South Africa it is restricted to the northern KwaZulu-Natal coast. Biological investigations revealed that it is a fast growing species that attains a maximum age of, 7 years. Males and females sexually matured in their third year. It has a protracted summer spawning season with evidence of serial spawning behaviour. T. botla is an opportunistic predator with a generalist diet, with fish feeding on a wide variety of prey items particularly those that are temporally ‘superabundant’. Small fish fed predominantly on copepods and terrestrial insects, whereas larger fish consumed bivalves and crabs. Teleosts, primarily engraulids, were important components to the diet of fish of all sizes. An ontogenetic dietary shift was observed just after sexual maturity (300-mm fork length) that is possibly linked to a change in habitat preference with larger fish foraging on deeper reefs.
- Full Text:
- Date Issued: 2015
Dynamic mitochondrial localisation of STAT3 in the cellular adipogenesis model 3T3-L1:
- Kramer, Adam H, Edkins, Adrienne L, Hoppe, Heinrich C, Prinsloo, Earl
- Authors: Kramer, Adam H , Edkins, Adrienne L , Hoppe, Heinrich C , Prinsloo, Earl
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/164885 , vital:41181 , DOI: 10.1002/jcb.25076
- Description: A mechanistic relationship exists between protein localisation, activity and cellular differentiation. Understanding the contribution of these molecular mechanisms is required for elucidation of conditions that drive development. Literature suggests non‐canonical translocation of the Signal Transducer and Activator of Transcription 3 (STAT3) to the mitochondria contributes to the regulation of the electron transport chain, cellular respiration and reactive oxygen species production. Based on this we investigated the role of mitochondrial STAT3, specifically the serine 727 phosphorylated form, in cellular differentiation using the well‐defined mouse adipogenic model 3T3-L1.
- Full Text:
- Date Issued: 2015
- Authors: Kramer, Adam H , Edkins, Adrienne L , Hoppe, Heinrich C , Prinsloo, Earl
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/164885 , vital:41181 , DOI: 10.1002/jcb.25076
- Description: A mechanistic relationship exists between protein localisation, activity and cellular differentiation. Understanding the contribution of these molecular mechanisms is required for elucidation of conditions that drive development. Literature suggests non‐canonical translocation of the Signal Transducer and Activator of Transcription 3 (STAT3) to the mitochondria contributes to the regulation of the electron transport chain, cellular respiration and reactive oxygen species production. Based on this we investigated the role of mitochondrial STAT3, specifically the serine 727 phosphorylated form, in cellular differentiation using the well‐defined mouse adipogenic model 3T3-L1.
- Full Text:
- Date Issued: 2015
Local institutions, actors, and natural resource governance in Kgalagadi Transfrontier Park and surrounds, South Africa
- Thondhlana, Gladman, Shackleton, Sheona E, Blignaut, James
- Authors: Thondhlana, Gladman , Shackleton, Sheona E , Blignaut, James
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67689 , vital:29130 , https://doi.org/10.1016/j.landusepol.2015.03.013
- Description: Publisher version , Crafting local institutions to allow more effective decision-making in the management of and access to natural resources in and beyond parks has long been considered key to collaborative governance. South Africa, in particular, has vigorously pursued collaborative governance as a desired approach to managing natural resources as evident in the new arrangements for previously restricted parks. However, though the discourse of collaborative governance has occupied conservation thinking and practice globally, few studies have looked at the interplay between local institutions, actors and collaborative governance involving indigenous hunter–gatherer communities in Southern Africa. In response, we assess the local actors and institutions that were put in place to facilitate collaborative governance of natural resources in the Kgalagadi Transfrontier Park and its surrounds in South Africa. Our findings show that though collaborative governance has a practical appeal, it is hampered by lack of participation in decision-making, information dissemination, transparency, trust and accountability, power relations, divergent interests and unequal access to natural resources. The findings also draw our attention to issues of heterogeneity, even within indigenous communities assumed to be homogenous by local conservation authorities as reflected in land settlement agreements in co-managed parks. We argue that collaborative governance arrangements need to reflect and be understood within the broader background of complex local realities.
- Full Text: false
- Date Issued: 2015
- Authors: Thondhlana, Gladman , Shackleton, Sheona E , Blignaut, James
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67689 , vital:29130 , https://doi.org/10.1016/j.landusepol.2015.03.013
- Description: Publisher version , Crafting local institutions to allow more effective decision-making in the management of and access to natural resources in and beyond parks has long been considered key to collaborative governance. South Africa, in particular, has vigorously pursued collaborative governance as a desired approach to managing natural resources as evident in the new arrangements for previously restricted parks. However, though the discourse of collaborative governance has occupied conservation thinking and practice globally, few studies have looked at the interplay between local institutions, actors and collaborative governance involving indigenous hunter–gatherer communities in Southern Africa. In response, we assess the local actors and institutions that were put in place to facilitate collaborative governance of natural resources in the Kgalagadi Transfrontier Park and its surrounds in South Africa. Our findings show that though collaborative governance has a practical appeal, it is hampered by lack of participation in decision-making, information dissemination, transparency, trust and accountability, power relations, divergent interests and unequal access to natural resources. The findings also draw our attention to issues of heterogeneity, even within indigenous communities assumed to be homogenous by local conservation authorities as reflected in land settlement agreements in co-managed parks. We argue that collaborative governance arrangements need to reflect and be understood within the broader background of complex local realities.
- Full Text: false
- Date Issued: 2015