A Change Project story: learning and caring for South Africa’s rivers
- Authors: Chetty, Preven
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/391060 , vital:68613 , xlink:href="https://eeasa.org.za/wp-content/uploads/2023/02/Final-EEASA-Bulletin-20212022-Final.pdf"
- Description: Water quality and scarcity is a major concern in Southern Africa and globally especially as the threat of climate change looms even closer. The current drought in South Africa and worsening rainfall has exposed the brittle nature of this country’s resilience to water shortages. Compounded to this is the fact that most rivers in South Africa are not adequately cared for and are under tremendous strain. Everyone who depends on these rivers whether directly or indirectly will soon be entering a new era where water will no longer be a ubiquitous commodity.
- Full Text:
- Date Issued: 2022
- Authors: Chetty, Preven
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/391060 , vital:68613 , xlink:href="https://eeasa.org.za/wp-content/uploads/2023/02/Final-EEASA-Bulletin-20212022-Final.pdf"
- Description: Water quality and scarcity is a major concern in Southern Africa and globally especially as the threat of climate change looms even closer. The current drought in South Africa and worsening rainfall has exposed the brittle nature of this country’s resilience to water shortages. Compounded to this is the fact that most rivers in South Africa are not adequately cared for and are under tremendous strain. Everyone who depends on these rivers whether directly or indirectly will soon be entering a new era where water will no longer be a ubiquitous commodity.
- Full Text:
- Date Issued: 2022
A laminated, emergentist view of skills ecosystems
- Ramsarup, Presha, Lotz-Sisitka, Heila, McGrath, Simon
- Authors: Ramsarup, Presha , Lotz-Sisitka, Heila , McGrath, Simon
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/370074 , vital:66295 , xlink:href="https://doi.org/10.1080/14767430.2022.2145768"
- Description: In this paper we present a model of vocational education and training (VET) that can be used to guide decisions relating to VET in Africa today. This model takes the critique of the neoclassical, neoliberal model of VET as its starting point. Guided by Bhaskar's Critical Naturalism, we use immanent critique to consider the adequacy of proposed alternatives to the neoclassical approach, such as: the heterodox approach, which foregrounds explanations based on human capital and political economy; and Hodgson and Spours' social ecosystem model, which addresses some of the limitations of the heterodox account by including, social and ecosystem elements. Finally, we offer a version of the social ecosystem model that, according to our analysis, explains more of the empirical evidence than previous models. Our version of the social ecosystem model differs from earlier versions in terms of its explicit reference to the critical realist ideas of position- practices and emergence.
- Full Text:
- Date Issued: 2022
- Authors: Ramsarup, Presha , Lotz-Sisitka, Heila , McGrath, Simon
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/370074 , vital:66295 , xlink:href="https://doi.org/10.1080/14767430.2022.2145768"
- Description: In this paper we present a model of vocational education and training (VET) that can be used to guide decisions relating to VET in Africa today. This model takes the critique of the neoclassical, neoliberal model of VET as its starting point. Guided by Bhaskar's Critical Naturalism, we use immanent critique to consider the adequacy of proposed alternatives to the neoclassical approach, such as: the heterodox approach, which foregrounds explanations based on human capital and political economy; and Hodgson and Spours' social ecosystem model, which addresses some of the limitations of the heterodox account by including, social and ecosystem elements. Finally, we offer a version of the social ecosystem model that, according to our analysis, explains more of the empirical evidence than previous models. Our version of the social ecosystem model differs from earlier versions in terms of its explicit reference to the critical realist ideas of position- practices and emergence.
- Full Text:
- Date Issued: 2022
A multiscale ONIOM study of the buckminsterfullerene (C60) Diels–Alder reaction: from model design to reaction path analysis
- Isamura, Bienfait K, Lobb, Kevin A
- Authors: Isamura, Bienfait K , Lobb, Kevin A
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/452517 , vital:75140 , xlink:href=" https://link.springer.com/article/10.1007/s00894-022-05319-0"
- Description: The hybrid ONIOM (Our own N-layered Integrated molecular Orbital and molecular Mechanics) formalism is employed to investigate the Diels–Alder reaction of the buckminsterfullerene C60. Our computa-tions suggest that the ONIOM2(M06-2X/6-31G(d): SVWN/STO3G) mod-el, enclosing both the diene and the pyracyclene fragment of C60 in the higher-layer, provides a reasonable trade-of between accuracy and computational cost as it comes to predicting reaction energetics. Moreover, the frontier molecular orbital (FMO) theory and activation strain model (ASM) are jointly relied on to rationalize the efect of –OH and –CN substituents on the activation barrier of this reaction. Finally, reaction paths are scrutinized to get insight into the various forces un-derpinning the process of cycloadduct formation.
- Full Text:
- Date Issued: 2022
- Authors: Isamura, Bienfait K , Lobb, Kevin A
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/452517 , vital:75140 , xlink:href=" https://link.springer.com/article/10.1007/s00894-022-05319-0"
- Description: The hybrid ONIOM (Our own N-layered Integrated molecular Orbital and molecular Mechanics) formalism is employed to investigate the Diels–Alder reaction of the buckminsterfullerene C60. Our computa-tions suggest that the ONIOM2(M06-2X/6-31G(d): SVWN/STO3G) mod-el, enclosing both the diene and the pyracyclene fragment of C60 in the higher-layer, provides a reasonable trade-of between accuracy and computational cost as it comes to predicting reaction energetics. Moreover, the frontier molecular orbital (FMO) theory and activation strain model (ASM) are jointly relied on to rationalize the efect of –OH and –CN substituents on the activation barrier of this reaction. Finally, reaction paths are scrutinized to get insight into the various forces un-derpinning the process of cycloadduct formation.
- Full Text:
- Date Issued: 2022
A simple quinoline-thiophene Schiff base turn-off chemosensor for Hg2+ detection
- Musikavanhu, Brian, Muthusamy, Selvaraj, Zhu, Dongwei, Xue, Zhaoli, Yu, Qian, Chivumba, Choonzo N, Mack, John, Nyokong, Tebello, Wang, Shengjun, Zhao, Long
- Authors: Musikavanhu, Brian , Muthusamy, Selvaraj , Zhu, Dongwei , Xue, Zhaoli , Yu, Qian , Chivumba, Choonzo N , Mack, John , Nyokong, Tebello , Wang, Shengjun , Zhao, Long
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/230362 , vital:49771 , xlink:href="https://doi.org/10.1016/j.saa.2021.120338"
- Description: A new Schiff base probe (QT) consisting of 8-aminoquinoline (Q) and thiophene-2-carboxaldehyde (T) moieties has been synthesized. QT undergoes chelation-enhanced fluorescence quenching when exposed to Hg2+ due to coordination by the sulfur and nitrogen atoms of QT thus forming a facile “turn-off” sensor. The formation of the chelation complex was confirmed by UV–visible absorption and emission spectral measurements, 1H NMR titration and density functional theory calculations. These studies revealed that the probe exhibits high selectivity and sensitivity towards Hg2+ in the presence of other common metal ions. A low detection limit of 23.4 nM was determined and a Job plot confirmed a 2:1 stoichiometry between QT and Hg2+. The potential utility of QT as a sensor for Hg2+ ions in human HeLa cells was determined by confocal fluorescence microscopy, and its suitability for use in the field with environmental samples was tested with Whatman filter paper strips.
- Full Text:
- Date Issued: 2022
- Authors: Musikavanhu, Brian , Muthusamy, Selvaraj , Zhu, Dongwei , Xue, Zhaoli , Yu, Qian , Chivumba, Choonzo N , Mack, John , Nyokong, Tebello , Wang, Shengjun , Zhao, Long
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/230362 , vital:49771 , xlink:href="https://doi.org/10.1016/j.saa.2021.120338"
- Description: A new Schiff base probe (QT) consisting of 8-aminoquinoline (Q) and thiophene-2-carboxaldehyde (T) moieties has been synthesized. QT undergoes chelation-enhanced fluorescence quenching when exposed to Hg2+ due to coordination by the sulfur and nitrogen atoms of QT thus forming a facile “turn-off” sensor. The formation of the chelation complex was confirmed by UV–visible absorption and emission spectral measurements, 1H NMR titration and density functional theory calculations. These studies revealed that the probe exhibits high selectivity and sensitivity towards Hg2+ in the presence of other common metal ions. A low detection limit of 23.4 nM was determined and a Job plot confirmed a 2:1 stoichiometry between QT and Hg2+. The potential utility of QT as a sensor for Hg2+ ions in human HeLa cells was determined by confocal fluorescence microscopy, and its suitability for use in the field with environmental samples was tested with Whatman filter paper strips.
- Full Text:
- Date Issued: 2022
A Sn (iv) porphyrin with mitochondria targeting properties for enhanced photodynamic activity against MCF-7 cells
- Babu, Balaji, Mack, John, Nyokong, Tebello
- Authors: Babu, Balaji , Mack, John , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/230897 , vital:49829 , xlink:href="https://doi.org/10.1039/D2NJ00350C"
- Description: Two readily synthesized Sn(IV) porphyrins (SnP, SnPH) have been prepared with and without the cationic triphenylphosphonium moiety (TPP+), which have high singlet oxygen quantum yields (ca. 0.72) and long triplet state lifetimes. The Sn(IV) porphyrin with a TPP+ moiety (SnPH) exhibits favorable photodynamic activity against MCF-7 cells with IC50 values of 2.9 μM. SnPH exhibits higher cellular uptake than SnP in MCF-7 cells. A Rhodamine 123 (Rh123) assay showed that SnPH targets mitochondria and induces apoptosis by generating reactive oxygen species. The results demonstrate that this structural modification strategy merits further in-depth study.
- Full Text:
- Date Issued: 2022
- Authors: Babu, Balaji , Mack, John , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/230897 , vital:49829 , xlink:href="https://doi.org/10.1039/D2NJ00350C"
- Description: Two readily synthesized Sn(IV) porphyrins (SnP, SnPH) have been prepared with and without the cationic triphenylphosphonium moiety (TPP+), which have high singlet oxygen quantum yields (ca. 0.72) and long triplet state lifetimes. The Sn(IV) porphyrin with a TPP+ moiety (SnPH) exhibits favorable photodynamic activity against MCF-7 cells with IC50 values of 2.9 μM. SnPH exhibits higher cellular uptake than SnP in MCF-7 cells. A Rhodamine 123 (Rh123) assay showed that SnPH targets mitochondria and induces apoptosis by generating reactive oxygen species. The results demonstrate that this structural modification strategy merits further in-depth study.
- Full Text:
- Date Issued: 2022
Adsorption of antibiotic-resistant bacteria and their cell-free deoxyribonucleic acid harbouring resistance genes in drinking water with metal oxides
- Authors: Tobechukwu, Anthony Eric
- Date: 2022
- Subjects: Metallic oxides , DNA -- Synthesis , Drinking water
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/27787 , vital:69494
- Description: Access to cleaner water is essential to human health. The incidence of Antibiotic Resistant Bacteria ARB in drinking water and subsequent proliferation of Antibiotic Resistance Genes ARGs in drinking water is a concern for public health. The free DNA cassette harboring antibiotic resistance gene in drinking water has been linked with impaired public health. The ARGs allows bacteria to develop resistance towards antibiotics while ARB render antibiotics ineffective. Existing drinking water treatment technologies eg adsorption, ozonation and chlorination, have shown different levels of potency in the removal of conventional water pollutant. These technologies, which operating principles is based on oxidation or mass transfer, have been explored to gained an insight into their efficiency in the removal of ARB ARGs in water treatment. In general, methods that functions by mass transfer of the ARB ARGs is more effectively than bacteria oxidation. Consequently, adsorption technology was chosen using common metal oxide adsorbents. The adsorbents ZnOAg CeO2 and Al2O3 were synthesized via the self propagation combustion method. This method was selected because of the purity of the final product and the energy requirement. One of the challenges in the removal of ARB in drinking water is the release of ARGs. To address this concern, five different ZnOAg heterostructures were synthesized for the removal of Enterococci faecium. ZnOAg was chosen because of the bactericidal and bacteriostatic characteristics. The study revealed that the concentration of the precursors influences the microstructures of the adsorbents; however, it did not significantly affect the adsorption efficiency. The maximum adsorption capacity q34.11 CFUg was obtained for Ag1Zn3.5. The kinetic studies revealed that Ag1Zn1 and Ag1Zn2 adsorbents agreed to the pseudofirst-order kinetic equation and adsorbents Ag2Zn1 Ag3.5Zn1 and Ag1Zn3.5 agreed to the pseudo-second-order kinetic equation. Initial tap-water pH range was beneficial for the adsorption and the pH of the treated tap-water was within the WHO tap water recommendation 6.5 – 8.5 whereas the effect of ionic strength, anionic and cationic interference was insignificant in the adsorption of MDREF onto the different heterostructure. Interestingly the MDREF could retain its cell membrane integrity and resistance genes, suggesting that surface adsorption was the primary mechanism for the removal. Cerium IV oxide CeO2 was selected because of high adsorption towards phosphate, backbone base for DNA. To prevent the problem of antibiotic resistance, we have synthesized a CeO2 adsorbent that exhibit highly positive character in a wide pH range, via the simple self-propagation combustion protocol, for the removal of free DNA harboring antibiotic resistance genes. Molecular characterization of the extracted genes showed that the sizes for E. coli and inherent gyrB genes are 147 and 460 bp with a purity between 19 2.0. The XRD SEM TEM, and PZC results of the as-synthesized CeO2 showed an agglomerate of pure cubic-faced centered material and highly crystalline, with a net charge at pH 6.2. Experimental results revealed that the reaction proceeded via pseudo first-order kinetic, and it is governed by electrostatic attraction. The free- DNA solution pH electrolyte, and competing ions impacted on the adsorption process. Further experimental results showed that the as-synthesized CeO2 adsorbent has the potential to be used for the removal of free DNA harboring ARGs from tap-water even under oxic conditions. Alumina Al2O3 is an abundant adsorbent that has also shown high removal capacity towards phosphate. The highly pure synthesized Al2O3 adsorbent exhibit fluid-like behaviour under Scanning Electron Microscope SEM. The XRD pattern corresponds to αAl2O3. The adsorption kinetics was described by pseudo second orderadsorption capacity 11.7 μgg implying chemisorption, which agrees with the electrostatic force of attraction caused by opposing ions. This result was evident by the effect of different ions in the tap water. The synthesized α-Al2O3 has the potential for the removal of cell free DNA harbouring multiply resistant genes. , Thesis (MSc) -- Faculty of Science and Agriculture, 2022
- Full Text:
- Date Issued: 2022
- Authors: Tobechukwu, Anthony Eric
- Date: 2022
- Subjects: Metallic oxides , DNA -- Synthesis , Drinking water
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/27787 , vital:69494
- Description: Access to cleaner water is essential to human health. The incidence of Antibiotic Resistant Bacteria ARB in drinking water and subsequent proliferation of Antibiotic Resistance Genes ARGs in drinking water is a concern for public health. The free DNA cassette harboring antibiotic resistance gene in drinking water has been linked with impaired public health. The ARGs allows bacteria to develop resistance towards antibiotics while ARB render antibiotics ineffective. Existing drinking water treatment technologies eg adsorption, ozonation and chlorination, have shown different levels of potency in the removal of conventional water pollutant. These technologies, which operating principles is based on oxidation or mass transfer, have been explored to gained an insight into their efficiency in the removal of ARB ARGs in water treatment. In general, methods that functions by mass transfer of the ARB ARGs is more effectively than bacteria oxidation. Consequently, adsorption technology was chosen using common metal oxide adsorbents. The adsorbents ZnOAg CeO2 and Al2O3 were synthesized via the self propagation combustion method. This method was selected because of the purity of the final product and the energy requirement. One of the challenges in the removal of ARB in drinking water is the release of ARGs. To address this concern, five different ZnOAg heterostructures were synthesized for the removal of Enterococci faecium. ZnOAg was chosen because of the bactericidal and bacteriostatic characteristics. The study revealed that the concentration of the precursors influences the microstructures of the adsorbents; however, it did not significantly affect the adsorption efficiency. The maximum adsorption capacity q34.11 CFUg was obtained for Ag1Zn3.5. The kinetic studies revealed that Ag1Zn1 and Ag1Zn2 adsorbents agreed to the pseudofirst-order kinetic equation and adsorbents Ag2Zn1 Ag3.5Zn1 and Ag1Zn3.5 agreed to the pseudo-second-order kinetic equation. Initial tap-water pH range was beneficial for the adsorption and the pH of the treated tap-water was within the WHO tap water recommendation 6.5 – 8.5 whereas the effect of ionic strength, anionic and cationic interference was insignificant in the adsorption of MDREF onto the different heterostructure. Interestingly the MDREF could retain its cell membrane integrity and resistance genes, suggesting that surface adsorption was the primary mechanism for the removal. Cerium IV oxide CeO2 was selected because of high adsorption towards phosphate, backbone base for DNA. To prevent the problem of antibiotic resistance, we have synthesized a CeO2 adsorbent that exhibit highly positive character in a wide pH range, via the simple self-propagation combustion protocol, for the removal of free DNA harboring antibiotic resistance genes. Molecular characterization of the extracted genes showed that the sizes for E. coli and inherent gyrB genes are 147 and 460 bp with a purity between 19 2.0. The XRD SEM TEM, and PZC results of the as-synthesized CeO2 showed an agglomerate of pure cubic-faced centered material and highly crystalline, with a net charge at pH 6.2. Experimental results revealed that the reaction proceeded via pseudo first-order kinetic, and it is governed by electrostatic attraction. The free- DNA solution pH electrolyte, and competing ions impacted on the adsorption process. Further experimental results showed that the as-synthesized CeO2 adsorbent has the potential to be used for the removal of free DNA harboring ARGs from tap-water even under oxic conditions. Alumina Al2O3 is an abundant adsorbent that has also shown high removal capacity towards phosphate. The highly pure synthesized Al2O3 adsorbent exhibit fluid-like behaviour under Scanning Electron Microscope SEM. The XRD pattern corresponds to αAl2O3. The adsorption kinetics was described by pseudo second orderadsorption capacity 11.7 μgg implying chemisorption, which agrees with the electrostatic force of attraction caused by opposing ions. This result was evident by the effect of different ions in the tap water. The synthesized α-Al2O3 has the potential for the removal of cell free DNA harbouring multiply resistant genes. , Thesis (MSc) -- Faculty of Science and Agriculture, 2022
- Full Text:
- Date Issued: 2022
African birds as army ant followers
- Authors: Craig, Adrian J F K
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448772 , vital:74759 , https://doi.org/10.1007/s10336-022-01987-0
- Description: Ant-following birds have been studied extensively in the Neotropics, but much less information is currently available for the Afrotropics. There are published records of 168 African bird species from 37 families foraging in association with driver ants (Dorylus, sub-family Dorylinae). However, of 52 bird species assessed as regular ant-followers, 38 belong to three families, which are disproportionately represented compared to other large Afrotropical bird families: Muscicapidae (18 spp.), Pycnonotidae (13 spp.) and Turdidae (7 spp.). The extent to which these birds are dependent on ants through their annual cycle is not known. African driver ants forage primarily under shaded, humid conditions by day, and may spend a month or longer underground. Conservation assessments of African forest habitats suggest that both driver ants and ant-following birds may be especially sensitive to the loss of forest cover.
- Full Text:
- Date Issued: 2022
- Authors: Craig, Adrian J F K
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448772 , vital:74759 , https://doi.org/10.1007/s10336-022-01987-0
- Description: Ant-following birds have been studied extensively in the Neotropics, but much less information is currently available for the Afrotropics. There are published records of 168 African bird species from 37 families foraging in association with driver ants (Dorylus, sub-family Dorylinae). However, of 52 bird species assessed as regular ant-followers, 38 belong to three families, which are disproportionately represented compared to other large Afrotropical bird families: Muscicapidae (18 spp.), Pycnonotidae (13 spp.) and Turdidae (7 spp.). The extent to which these birds are dependent on ants through their annual cycle is not known. African driver ants forage primarily under shaded, humid conditions by day, and may spend a month or longer underground. Conservation assessments of African forest habitats suggest that both driver ants and ant-following birds may be especially sensitive to the loss of forest cover.
- Full Text:
- Date Issued: 2022
Age and growth of the Cape knifejaw Oplegnathus conwayi, an endemic South African teleost
- Foster, Ryan M, Childs, Amber-Robyn, Mann, Bruce Q, Potts, Warren M
- Authors: Foster, Ryan M , Childs, Amber-Robyn , Mann, Bruce Q , Potts, Warren M
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/443128 , vital:74080 , https://doi.org/10.1080/15627020.2022.2035254
- Description: The South African spearfishery targets a variety of data-deficient species, which are consequently poorly managed. This study aimed to describe the age and growth of one of these species, the Cape knifejaw, Oplegnathus conwayi, which is endemic to the southern and eastern coasts of South Africa. Monthly biological samples were collected through research spearfishing (n = 170) and augmented by recreational spearfishers’ catches (n = 135). The results indicated that the O. conwayi population sex ratio was skewed towards males (1M:0.6F). The length- and age-frequency distributions were similar between sexes. Oplegnathus conwayi is a relatively slow-growing species, with a maximum-recorded age of 27 years. No significant differences were observed between male and female growth, with the overall population growth curve being best described as L(t) = 697.15(1 − e−0.06(t−6.30)). The slow growth observed in this species is characteristic of a species that is vulnerable to overexploitation, and accordingly a precautionary approach to future management is recommended.
- Full Text:
- Date Issued: 2022
- Authors: Foster, Ryan M , Childs, Amber-Robyn , Mann, Bruce Q , Potts, Warren M
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/443128 , vital:74080 , https://doi.org/10.1080/15627020.2022.2035254
- Description: The South African spearfishery targets a variety of data-deficient species, which are consequently poorly managed. This study aimed to describe the age and growth of one of these species, the Cape knifejaw, Oplegnathus conwayi, which is endemic to the southern and eastern coasts of South Africa. Monthly biological samples were collected through research spearfishing (n = 170) and augmented by recreational spearfishers’ catches (n = 135). The results indicated that the O. conwayi population sex ratio was skewed towards males (1M:0.6F). The length- and age-frequency distributions were similar between sexes. Oplegnathus conwayi is a relatively slow-growing species, with a maximum-recorded age of 27 years. No significant differences were observed between male and female growth, with the overall population growth curve being best described as L(t) = 697.15(1 − e−0.06(t−6.30)). The slow growth observed in this species is characteristic of a species that is vulnerable to overexploitation, and accordingly a precautionary approach to future management is recommended.
- Full Text:
- Date Issued: 2022
Alignment, scaling and resourcing of citizen-based water quality monitoring Initiatives
- Lotz-Sisitka, Heila, Ward, Mike, Taylor, Jim, Vallabh, Priya, Madiba, Morakane, Graham, P Mark, Louw, Adrienne J, Brownell, Faye
- Authors: Lotz-Sisitka, Heila , Ward, Mike , Taylor, Jim , Vallabh, Priya , Madiba, Morakane , Graham, P Mark , Louw, Adrienne J , Brownell, Faye
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/435729 , vital:73195 , ISBN 978-0-6392-0344-7 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2854%20final.pdf
- Description: This action-oriented research project seeks to address the policy-practice contradiction that exists between commit-ments and requirements for citizen engagement and in-volvement in Integrated Water Quality Management (IWQM) and a lack of sustainable support for scaling high quality Citi-zen-based Water Quality Monitoring (CBWQM) practices that exist in South Africa.
- Full Text:
- Date Issued: 2022
- Authors: Lotz-Sisitka, Heila , Ward, Mike , Taylor, Jim , Vallabh, Priya , Madiba, Morakane , Graham, P Mark , Louw, Adrienne J , Brownell, Faye
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/435729 , vital:73195 , ISBN 978-0-6392-0344-7 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2854%20final.pdf
- Description: This action-oriented research project seeks to address the policy-practice contradiction that exists between commit-ments and requirements for citizen engagement and in-volvement in Integrated Water Quality Management (IWQM) and a lack of sustainable support for scaling high quality Citi-zen-based Water Quality Monitoring (CBWQM) practices that exist in South Africa.
- Full Text:
- Date Issued: 2022
AMANZI For Food
- Lotz-Sisitka, Heila, Pesanayi, Tichaona, Sisitka, Lawrence, Metelerkamp, Luke, Chakona, Gamuchirai, van Staden, Wilma, Durr, Sarah, Matiwane, Mandelive, Maqwelane, Lwande, Conde-Aller, Laura, Shawarire, Patience
- Authors: Lotz-Sisitka, Heila , Pesanayi, Tichaona , Sisitka, Lawrence , Metelerkamp, Luke , Chakona, Gamuchirai , van Staden, Wilma , Durr, Sarah , Matiwane, Mandelive , Maqwelane, Lwande , Conde-Aller, Laura , Shawarire, Patience
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/435745 , vital:73197 , ISBN 978-0-6392-0309-6 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/TT%20868%20final%20web.pdf
- Description: This action-oriented research project seeks to address the policy-practice contradiction that exists between commit-ments and requirements for citizen engagement and in-volvement in Integrated Water Quality Management (IWQM) and a lack of sustainable support for scaling high quality Citi-zen-based Water Quality Monitoring (CBWQM) practices that exist in South Africa.
- Full Text:
- Date Issued: 2022
- Authors: Lotz-Sisitka, Heila , Pesanayi, Tichaona , Sisitka, Lawrence , Metelerkamp, Luke , Chakona, Gamuchirai , van Staden, Wilma , Durr, Sarah , Matiwane, Mandelive , Maqwelane, Lwande , Conde-Aller, Laura , Shawarire, Patience
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/435745 , vital:73197 , ISBN 978-0-6392-0309-6 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/TT%20868%20final%20web.pdf
- Description: This action-oriented research project seeks to address the policy-practice contradiction that exists between commit-ments and requirements for citizen engagement and in-volvement in Integrated Water Quality Management (IWQM) and a lack of sustainable support for scaling high quality Citi-zen-based Water Quality Monitoring (CBWQM) practices that exist in South Africa.
- Full Text:
- Date Issued: 2022
Analysing the Impact of Extended Curriculum Programmes: Implications for Theory, Design and Practice
- Authors: Boughey, Chrissie
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/434453 , vital:73063 , ISBN 9781991201737 , https://africansunmedia.store.it.si/ZA/book/extended-curriculum-programmes-challenges-and-opportunities/1199327
- Description: The introduction of ECPs in South African Universities is seen by many as South Africa’s key strategy for addressing the problem of poor patterns of student success and has its basis on the uncontested acceptance that an extended study duration may be necessary to bring some categories of learners to a level of parity with the readiness expectations of their course of study. Even so, this transformative strategic imperative has been plagued by a range of challenges that include poor systems readiness; poor selection mechanisms in the identification of ECP students; poor numeracy and literacy amongst students, and indifferent teacher involvement in ECPs. This volume offers a rare insight into many of the above-recognised challenges and in so doing provides critical matter for thought for educators within the higher education sector.
- Full Text:
- Date Issued: 2022
Analysing the Impact of Extended Curriculum Programmes: Implications for Theory, Design and Practice
- Authors: Boughey, Chrissie
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/434453 , vital:73063 , ISBN 9781991201737 , https://africansunmedia.store.it.si/ZA/book/extended-curriculum-programmes-challenges-and-opportunities/1199327
- Description: The introduction of ECPs in South African Universities is seen by many as South Africa’s key strategy for addressing the problem of poor patterns of student success and has its basis on the uncontested acceptance that an extended study duration may be necessary to bring some categories of learners to a level of parity with the readiness expectations of their course of study. Even so, this transformative strategic imperative has been plagued by a range of challenges that include poor systems readiness; poor selection mechanisms in the identification of ECP students; poor numeracy and literacy amongst students, and indifferent teacher involvement in ECPs. This volume offers a rare insight into many of the above-recognised challenges and in so doing provides critical matter for thought for educators within the higher education sector.
- Full Text:
- Date Issued: 2022
Application of gold and palladium nanoparticles supported on polymelamine microspheres in the oxidation of 1-phenylethanol and some other phenyl substituted alcohols
- Storm, Ené, Maggott, Emile D, Mashazi, Philani N, Nyokong, Tebello, Malgas-Enus, Rehana, Mapolie, Selwyn F
- Authors: Storm, Ené , Maggott, Emile D , Mashazi, Philani N , Nyokong, Tebello , Malgas-Enus, Rehana , Mapolie, Selwyn F
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/299824 , vital:57858 , xlink:href="https://doi.org/10.1016/j.mcat.2022.112456"
- Description: Melamine formaldehyde and melamine resorcinol formaldehyde microspheres were decorated with Au and Pd nanoparticles and applied as heterogeneous catalysts in the oxidation of 1-phenylethanol. The catalysts showed similar activities irrespective of the support employed. Moderate conversion activities of 48–50% were achieved when using acetonitrile as solvent; however, when employing water as solvent, the supported catalysts formed a three-phase, emulsion system which facilitated the catalytic conversion of 1-phenylethanol to acetophenone at much higher conversions of around 83%. The oxidant, TBHP, decomposed rapidly in acetonitrile, whilst it remained stable in aqueous solution, leading to the enhanced activities observed when using water as solvent. These systems also proved to be recyclable for up to five cycles, with only slight loss of activity observed; this can be attributed to the physical loss of catalyst during the workup procedure conducted between each cycle.
- Full Text:
- Date Issued: 2022
- Authors: Storm, Ené , Maggott, Emile D , Mashazi, Philani N , Nyokong, Tebello , Malgas-Enus, Rehana , Mapolie, Selwyn F
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/299824 , vital:57858 , xlink:href="https://doi.org/10.1016/j.mcat.2022.112456"
- Description: Melamine formaldehyde and melamine resorcinol formaldehyde microspheres were decorated with Au and Pd nanoparticles and applied as heterogeneous catalysts in the oxidation of 1-phenylethanol. The catalysts showed similar activities irrespective of the support employed. Moderate conversion activities of 48–50% were achieved when using acetonitrile as solvent; however, when employing water as solvent, the supported catalysts formed a three-phase, emulsion system which facilitated the catalytic conversion of 1-phenylethanol to acetophenone at much higher conversions of around 83%. The oxidant, TBHP, decomposed rapidly in acetonitrile, whilst it remained stable in aqueous solution, leading to the enhanced activities observed when using water as solvent. These systems also proved to be recyclable for up to five cycles, with only slight loss of activity observed; this can be attributed to the physical loss of catalyst during the workup procedure conducted between each cycle.
- Full Text:
- Date Issued: 2022
Aptamer versus antibody as probes for the impedimetric biosensor for human epidermal growth factor receptor
- Centane, Sixolile, Nyokong, Tebello
- Authors: Centane, Sixolile , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/229884 , vital:49720 , xlink:href="https://doi.org/10.1016/j.jinorgbio.2022.111764"
- Description: In the present work, the performance of aptamer and antibody bioreceptors for the detection of the human epidermal growth factor receptor (HER2) cancer biomarker on a glassy carbon electrode is reported. The carboxylic acid group rich graphene quantum dots (GQDs) modified with gold nanoparticles and a porphyrin binuclear framework (CoP-BNF) were used to modify the glassy carbon electrode. The aptamer and antibody were both amine functionalized and attached to GQDs and CoP-BNF through an amide bond. The designed immunosensors and aptasensors in this work were characterized using electrochemical impedance spectroscopy. The aptasensors, compared to the immunosensors gave better limit of detection values. The aptasensor outperforms the immunosensor in terms of its reusability and storability, while the immunosensor could not be regenerated for subsequent experiments. The potential applicability of all sensors in this work was also investigated, by detection of HER2 in spiked human serum with acceptable results.
- Full Text:
- Date Issued: 2022
- Authors: Centane, Sixolile , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/229884 , vital:49720 , xlink:href="https://doi.org/10.1016/j.jinorgbio.2022.111764"
- Description: In the present work, the performance of aptamer and antibody bioreceptors for the detection of the human epidermal growth factor receptor (HER2) cancer biomarker on a glassy carbon electrode is reported. The carboxylic acid group rich graphene quantum dots (GQDs) modified with gold nanoparticles and a porphyrin binuclear framework (CoP-BNF) were used to modify the glassy carbon electrode. The aptamer and antibody were both amine functionalized and attached to GQDs and CoP-BNF through an amide bond. The designed immunosensors and aptasensors in this work were characterized using electrochemical impedance spectroscopy. The aptasensors, compared to the immunosensors gave better limit of detection values. The aptasensor outperforms the immunosensor in terms of its reusability and storability, while the immunosensor could not be regenerated for subsequent experiments. The potential applicability of all sensors in this work was also investigated, by detection of HER2 in spiked human serum with acceptable results.
- Full Text:
- Date Issued: 2022
Artisanal mining versus sustainability of agricultural food supply chains: effects of the conflicts in Southern Zimbabwe
- Chari, Felix, Novukela, Cawe, Ngcamu , Bethuel Sibongiseni
- Authors: Chari, Felix , Novukela, Cawe , Ngcamu , Bethuel Sibongiseni
- Date: 2022
- Subjects: Traditional farming Small Scale mining Great Zimbabwe Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7082 , vital:52810 , xlink:href="https://doi.org/10.1080/23311886.2021.2002542"
- Description: This article seeks to establish the social and environmental consequences of artisanal mining on economic sustainability of agricultural food supply chains in Zimbabwe. Following a descriptive research design, interviews were conducted with 36 farmers. Interviewees were purposively sampled from potential respondents in Southern Zimbabwe. Interview results were triangulated with data from published reports and newspaper articles. Data was analysed using NVivo application version 12 and presented in vignettes. The results of this study are useful to artisanal miners, farmers, and government. Recommendations for further studies are given. KEYWORDS: Artisanal mining farmers food supply chains Zimbabwe sustainability
- Full Text:
- Date Issued: 2022
- Authors: Chari, Felix , Novukela, Cawe , Ngcamu , Bethuel Sibongiseni
- Date: 2022
- Subjects: Traditional farming Small Scale mining Great Zimbabwe Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7082 , vital:52810 , xlink:href="https://doi.org/10.1080/23311886.2021.2002542"
- Description: This article seeks to establish the social and environmental consequences of artisanal mining on economic sustainability of agricultural food supply chains in Zimbabwe. Following a descriptive research design, interviews were conducted with 36 farmers. Interviewees were purposively sampled from potential respondents in Southern Zimbabwe. Interview results were triangulated with data from published reports and newspaper articles. Data was analysed using NVivo application version 12 and presented in vignettes. The results of this study are useful to artisanal miners, farmers, and government. Recommendations for further studies are given. KEYWORDS: Artisanal mining farmers food supply chains Zimbabwe sustainability
- Full Text:
- Date Issued: 2022
Assessing climate risk to support urban forests in a changing climate
- Esperon-Rodriguez, Manuel, Rymer, Paul D, Power, Sally A, Barton, David N, Cariñanos, Paloma, Dobbs, Cynnamon, Eleuterio, Ana A, Escobedo, Francisco J, Hauer, Richard, Hermy, Martin, Jahani, Ali, Onyekwelu, Jonathan C, Östberg, Johan, Pataki, Diane, Randrup, Thomas B, Rasmussen, Tørres, Roman, Lara A, Russo, Alessio, Shackleton, Charlie M, Solfjeld, Ingjerd, van Doorn, Natalie S, Wells, Matthew J, Wiström, Björn, Yan, Pengbo, Yang, Jun, Tjoelker, Mark G
- Authors: Esperon-Rodriguez, Manuel , Rymer, Paul D , Power, Sally A , Barton, David N , Cariñanos, Paloma , Dobbs, Cynnamon , Eleuterio, Ana A , Escobedo, Francisco J , Hauer, Richard , Hermy, Martin , Jahani, Ali , Onyekwelu, Jonathan C , Östberg, Johan , Pataki, Diane , Randrup, Thomas B , Rasmussen, Tørres , Roman, Lara A , Russo, Alessio , Shackleton, Charlie M , Solfjeld, Ingjerd , van Doorn, Natalie S , Wells, Matthew J , Wiström, Björn , Yan, Pengbo , Yang, Jun , Tjoelker, Mark G
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/402191 , vital:69829 , xlink:href="https://doi.org/10.1002/ppp3.10240"
- Description: Globally, cities are planning for resilience through urban greening initiatives as governments understand the importance of urban forests in improving quality of life and mitigating climate change. However, the persistence of urban forests and the ecosystem benefits they provide are threatened by climate change, and systematic assessments of causes of tree dieback and mortality in urban environments are rare. Long-term monitoring studies and adaptive management are needed to identify and prevent climate change-driven failures and mortality. Research and monitoring when coupled with systematic forecasting will enable governments to incorporate climate change resilience into urban forestry planning. Future scenarios in which urban forests are resilient or in decline will depend on the management and planning actions we make today.
- Full Text:
- Date Issued: 2022
- Authors: Esperon-Rodriguez, Manuel , Rymer, Paul D , Power, Sally A , Barton, David N , Cariñanos, Paloma , Dobbs, Cynnamon , Eleuterio, Ana A , Escobedo, Francisco J , Hauer, Richard , Hermy, Martin , Jahani, Ali , Onyekwelu, Jonathan C , Östberg, Johan , Pataki, Diane , Randrup, Thomas B , Rasmussen, Tørres , Roman, Lara A , Russo, Alessio , Shackleton, Charlie M , Solfjeld, Ingjerd , van Doorn, Natalie S , Wells, Matthew J , Wiström, Björn , Yan, Pengbo , Yang, Jun , Tjoelker, Mark G
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/402191 , vital:69829 , xlink:href="https://doi.org/10.1002/ppp3.10240"
- Description: Globally, cities are planning for resilience through urban greening initiatives as governments understand the importance of urban forests in improving quality of life and mitigating climate change. However, the persistence of urban forests and the ecosystem benefits they provide are threatened by climate change, and systematic assessments of causes of tree dieback and mortality in urban environments are rare. Long-term monitoring studies and adaptive management are needed to identify and prevent climate change-driven failures and mortality. Research and monitoring when coupled with systematic forecasting will enable governments to incorporate climate change resilience into urban forestry planning. Future scenarios in which urban forests are resilient or in decline will depend on the management and planning actions we make today.
- Full Text:
- Date Issued: 2022
Assessing the electrocatalytic activity of a localized push-pull system in cobalt phthalocyanine/graphene quantum dot hybrids
- Nkhahle, Reitumetse, Nyokong, Tebello
- Authors: Nkhahle, Reitumetse , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/229909 , vital:49722 , xlink:href="https://doi.org/10.1016/j.matchemphys.2022.125842"
- Description: In this study, two cobalt phthalocyanines (asymmetric complex 1) and symmetric (complex 2) were synthesized and conjugated to nitrogen-doped graphene quantum dots (NGQDs) through covalent and non-covalent means to create Co phthalocyanine (CoPc)-NGQDs hybrid systems. The CoPcs and conjugates were applied as electrode modifiers on a glassy carbon electrode in the electrochemical sensing of nitrite. Of the CoPcs alone, complex 1 performed better than complex 2 regarding the limits of detection (LoD) recorded (5.74 μM for 1 and 15.1 μM for 2). Regarding the conjugates/nanocomposites, the π-π stacked conjugate derived from complex 2 (2πNGQDs) demonstrated highly favourable electrochemical potential with an LoD value of 0.70 μM. The nanocomposites fashioned from complex 1 were marred by a reduced loading which rendered the conjugates poor electrochemical sensors. These observations however do not disqualify GQDs as complementary nanomaterials to phthalocyanines but rather shed light on seeking alternative routes to increasing the Pc loading in conjugates (more so in π-π stacked conjugates).
- Full Text:
- Date Issued: 2022
- Authors: Nkhahle, Reitumetse , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/229909 , vital:49722 , xlink:href="https://doi.org/10.1016/j.matchemphys.2022.125842"
- Description: In this study, two cobalt phthalocyanines (asymmetric complex 1) and symmetric (complex 2) were synthesized and conjugated to nitrogen-doped graphene quantum dots (NGQDs) through covalent and non-covalent means to create Co phthalocyanine (CoPc)-NGQDs hybrid systems. The CoPcs and conjugates were applied as electrode modifiers on a glassy carbon electrode in the electrochemical sensing of nitrite. Of the CoPcs alone, complex 1 performed better than complex 2 regarding the limits of detection (LoD) recorded (5.74 μM for 1 and 15.1 μM for 2). Regarding the conjugates/nanocomposites, the π-π stacked conjugate derived from complex 2 (2πNGQDs) demonstrated highly favourable electrochemical potential with an LoD value of 0.70 μM. The nanocomposites fashioned from complex 1 were marred by a reduced loading which rendered the conjugates poor electrochemical sensors. These observations however do not disqualify GQDs as complementary nanomaterials to phthalocyanines but rather shed light on seeking alternative routes to increasing the Pc loading in conjugates (more so in π-π stacked conjugates).
- Full Text:
- Date Issued: 2022
Assessing the Impact of DNS Configuration on Low Bandwidth Networks
- Okuthe, J A, Terzoli, Alfredo
- Authors: Okuthe, J A , Terzoli, Alfredo
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430903 , vital:72726 , https://doi.org/10.1007/978-3-031-34896-9_6
- Description: Domain name system (DNS) is an essential enabler for connecting us-ers and services on the Internet. DNS translates human readable do-main names into IP addresses and precedes client connection to a server via a domain name. DNS service is therefore expected to con-sume network bandwidth even though it offers no direct benefit to the user. Having observed the large component of DNS traffic on the com-munity network local loop in our previous study, we migrated the DNS service from a server on the LAN to the gateway router and reconfig-ured the cache time-to-live. Results from the analysis of network traffic captured from the gateway router interface show a 26% decrease in the downlink bandwidth utilization and 46% decline in the uplink bandwidth utilization. The DNS component of the local loop traffic reduces from 45.28% to 4.11%. On the other hand, the Web component of the local loop traffic increases from 49.42% to 95.49%. Data collected from a mirroring port on the LAN switch indicate a decrease in the DNS portion of the internal traffic from 0.38% to 0.18%. Although the DNS reconfigu-ration helps alleviate network bandwidth constraints and reduces DNS component of the traffic, the Web portion increases. The implementa-tion of effective, efficient and sustainable Web traffic management is therefore required.
- Full Text:
- Date Issued: 2022
- Authors: Okuthe, J A , Terzoli, Alfredo
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430903 , vital:72726 , https://doi.org/10.1007/978-3-031-34896-9_6
- Description: Domain name system (DNS) is an essential enabler for connecting us-ers and services on the Internet. DNS translates human readable do-main names into IP addresses and precedes client connection to a server via a domain name. DNS service is therefore expected to con-sume network bandwidth even though it offers no direct benefit to the user. Having observed the large component of DNS traffic on the com-munity network local loop in our previous study, we migrated the DNS service from a server on the LAN to the gateway router and reconfig-ured the cache time-to-live. Results from the analysis of network traffic captured from the gateway router interface show a 26% decrease in the downlink bandwidth utilization and 46% decline in the uplink bandwidth utilization. The DNS component of the local loop traffic reduces from 45.28% to 4.11%. On the other hand, the Web component of the local loop traffic increases from 49.42% to 95.49%. Data collected from a mirroring port on the LAN switch indicate a decrease in the DNS portion of the internal traffic from 0.38% to 0.18%. Although the DNS reconfigu-ration helps alleviate network bandwidth constraints and reduces DNS component of the traffic, the Web portion increases. The implementa-tion of effective, efficient and sustainable Web traffic management is therefore required.
- Full Text:
- Date Issued: 2022
Asymmetrical zinc (II) phthalocyanines conjugated to metal tungstate nanoparticles for photoinactivation of Staphylococcus aureus
- Mgidlana, Sithi, Managa, Muthumuni, Nyokong, Tebello
- Authors: Mgidlana, Sithi , Managa, Muthumuni , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/295718 , vital:57372 , xlink:href="https://doi.org/10.1080/00958972.2022.2090837"
- Description: In this study, we report for the first time on the photodynamic antimicrobial chemotherapy (PACT) of asymmetrical zinc(II) phthalocyanines and their conjugates with nickel tungstate (NiWO4), cobalt tungstate (CoWO4) and bismuth tungstate (Bi2WO6) nanoparticles. CoWO4, NiWO4 and Bi2WO6 were capped with glutathione and covalently linked to three asymmetrical zinc(II) phthalocyanines for PACT. The plate count method was used to investigate the effect of covalently linking asymmetrical zinc(II) phthalocyanines to nanoparticles under light (for PACT against Staphylococcus aureus) and in the dark. Both Pc complexes and the conjugates indicated minimum dark-toxicity. The conjugates showed greater antimicrobial activity against a gram-positive and drug resistant bacteria, Staphylococcus aureus, than Pc complexes alone.
- Full Text:
- Date Issued: 2022
- Authors: Mgidlana, Sithi , Managa, Muthumuni , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/295718 , vital:57372 , xlink:href="https://doi.org/10.1080/00958972.2022.2090837"
- Description: In this study, we report for the first time on the photodynamic antimicrobial chemotherapy (PACT) of asymmetrical zinc(II) phthalocyanines and their conjugates with nickel tungstate (NiWO4), cobalt tungstate (CoWO4) and bismuth tungstate (Bi2WO6) nanoparticles. CoWO4, NiWO4 and Bi2WO6 were capped with glutathione and covalently linked to three asymmetrical zinc(II) phthalocyanines for PACT. The plate count method was used to investigate the effect of covalently linking asymmetrical zinc(II) phthalocyanines to nanoparticles under light (for PACT against Staphylococcus aureus) and in the dark. Both Pc complexes and the conjugates indicated minimum dark-toxicity. The conjugates showed greater antimicrobial activity against a gram-positive and drug resistant bacteria, Staphylococcus aureus, than Pc complexes alone.
- Full Text:
- Date Issued: 2022
Austral birds offer insightful complementary models in ecology and evolution
- Theuerkauf, Jörn, Villavicencio, Camilla P, Adreani, Nicholas M, Attisano, Alfredo, Craig, Adrian J F K, D’Amelio, Pietro B, Gula, Roman, Lee, Alan T K, Mentesana, Lucia, Quillfeldt, Petra, Quirici, Veronica, Quispe, René, Vásquez, Rodrigo A, Wingfield, John C, Masello, Juan F
- Authors: Theuerkauf, Jörn , Villavicencio, Camilla P , Adreani, Nicholas M , Attisano, Alfredo , Craig, Adrian J F K , D’Amelio, Pietro B , Gula, Roman , Lee, Alan T K , Mentesana, Lucia , Quillfeldt, Petra , Quirici, Veronica , Quispe, René , Vásquez, Rodrigo A , Wingfield, John C , Masello, Juan F
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449097 , vital:74788 , https://www.cell.com/trends/ecology-evolution/fulltext/S0169-5347(22)00114-8
- Description: The Southern Hemisphere differs from the Northern Hemisphere in many aspects. However, most ecological and evolutionary research is conducted in the Northern Hemisphere and its conclusions are extrapolated to the entire globe. Therefore, unique organismal and evolutionary characteristics of the south are overlooked. We use ornithology to show the importance of including a southern perspective. We present examples of plumage pigmentation, brood-parasitic nestling ejection, flightlessness, female song, and female aggression modulated by progesterone as complementary models for investigating fundamental biological questions. More research in the Southern Hemisphere, together with increased cooperation among researchers across the hemispheres and within the Southern Hemisphere, will provide a greater global outlook into ecology and evolution.
- Full Text:
- Date Issued: 2022
- Authors: Theuerkauf, Jörn , Villavicencio, Camilla P , Adreani, Nicholas M , Attisano, Alfredo , Craig, Adrian J F K , D’Amelio, Pietro B , Gula, Roman , Lee, Alan T K , Mentesana, Lucia , Quillfeldt, Petra , Quirici, Veronica , Quispe, René , Vásquez, Rodrigo A , Wingfield, John C , Masello, Juan F
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449097 , vital:74788 , https://www.cell.com/trends/ecology-evolution/fulltext/S0169-5347(22)00114-8
- Description: The Southern Hemisphere differs from the Northern Hemisphere in many aspects. However, most ecological and evolutionary research is conducted in the Northern Hemisphere and its conclusions are extrapolated to the entire globe. Therefore, unique organismal and evolutionary characteristics of the south are overlooked. We use ornithology to show the importance of including a southern perspective. We present examples of plumage pigmentation, brood-parasitic nestling ejection, flightlessness, female song, and female aggression modulated by progesterone as complementary models for investigating fundamental biological questions. More research in the Southern Hemisphere, together with increased cooperation among researchers across the hemispheres and within the Southern Hemisphere, will provide a greater global outlook into ecology and evolution.
- Full Text:
- Date Issued: 2022
Backpack carriage and musculoskeletal pain among primary school learners in King Williams Town, South Africa
- Authors: Moni, Busisiwe
- Date: 2022
- Subjects: Backache -- Prevention , Pediatric rheumatology , Pain -- Treatment
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/26984 , vital:66208
- Description: BACKGROUND: There is rising concern that kids are walking to school with too much weight on their backs. The weight of schoolchildren's backpacks is a persistent and divisive topic in the fields of education and health. Children who carry heavy backpacks are more likely to have back discomfort and musculoskeletal pain, which raises their risk of developing chronic back pain as adults. There is little research on this topic among South African school-age youngsters. The goal of the study was to find out how common low back and other musculoskeletal complaints were among primary school students who used a school bag. RESEARCH AIM: The purpose of the study was to identify the prevalence and location of musculoskeletal discomfort in primary school students in King William's Town, South Africa, and describe their link with backpack use. METHOD: In King Williams Town, Eastern Cape, South Africa, a descriptive cross-sectional survey was conducted among elementary school students between the ages of 9 and 14 years old. A systematic questionnaire and the Cornell Musculoskeletal Questionnaire were used to gather the data (body chart). Age, gender, and schoolbag details (style of backpack, carrying technique, and carrying time) were collected. The learner's waist, hip, and bag circumferences were all measured. On the data, descriptive and interferential statistics were used. FINDINGS: The study's conclusions showed that students' musculoskeletal pain was brought on by the weight of their backpacks or school bags. The majority of the students (89.8percent) complain about the difficulty they experience when lugging their heavy backpacks to class. In addition, 83.4percent of the students had bags that weighed more than 10percent of their body weight. Additionally, a sizable percentage of students (89.8percent) carry a hefty bag to school every day and report feeling fatigued while doing so (90.8percent). 90percent of the students reported feeling discomfort before, during, or after carrying their schoolbags. This pain is related with carrying a schoolbag. The majority of students (53.5percent) felt that their daily pain interferes with their ability to study. In order of severity, the majority of students report having discomfort in their shoulders (82.7percent), lower back (59.9percent), neck (47.0percent), upper back (40.7percent), and upper arm (16.4percent). CONCLUSION: According to the study, there is a link between students' musculoskeletal pain and carrying hefty backpacks or school bags. The shoulders are where musculoskeletal discomfort is most frequently felt. The study supported the findings of the majority of studies cited in the literature that most schoolchildren suffer from musculoskeletal pain because the weight of their backpacks is excessive compared to their size, weight, and age. RECOMMENDATIONS: The study produced a number of recommendations, including that the Department of Basic Education inform teachers, students, parents, guardians, and other key stakeholders about the effects of heavy backpacks or schoolbags on students' musculoskeletal pain. For students' convenience and to lighten the load on their school bags, locker rooms should be available. Teachers, parents, and guardians should also pay attention to the school bags that students are using to make sure that the weight is appropriate for their age and body size. , Thesis (MPA) -- Faculty of Health Sciences, 2022
- Full Text:
- Date Issued: 2022
- Authors: Moni, Busisiwe
- Date: 2022
- Subjects: Backache -- Prevention , Pediatric rheumatology , Pain -- Treatment
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/26984 , vital:66208
- Description: BACKGROUND: There is rising concern that kids are walking to school with too much weight on their backs. The weight of schoolchildren's backpacks is a persistent and divisive topic in the fields of education and health. Children who carry heavy backpacks are more likely to have back discomfort and musculoskeletal pain, which raises their risk of developing chronic back pain as adults. There is little research on this topic among South African school-age youngsters. The goal of the study was to find out how common low back and other musculoskeletal complaints were among primary school students who used a school bag. RESEARCH AIM: The purpose of the study was to identify the prevalence and location of musculoskeletal discomfort in primary school students in King William's Town, South Africa, and describe their link with backpack use. METHOD: In King Williams Town, Eastern Cape, South Africa, a descriptive cross-sectional survey was conducted among elementary school students between the ages of 9 and 14 years old. A systematic questionnaire and the Cornell Musculoskeletal Questionnaire were used to gather the data (body chart). Age, gender, and schoolbag details (style of backpack, carrying technique, and carrying time) were collected. The learner's waist, hip, and bag circumferences were all measured. On the data, descriptive and interferential statistics were used. FINDINGS: The study's conclusions showed that students' musculoskeletal pain was brought on by the weight of their backpacks or school bags. The majority of the students (89.8percent) complain about the difficulty they experience when lugging their heavy backpacks to class. In addition, 83.4percent of the students had bags that weighed more than 10percent of their body weight. Additionally, a sizable percentage of students (89.8percent) carry a hefty bag to school every day and report feeling fatigued while doing so (90.8percent). 90percent of the students reported feeling discomfort before, during, or after carrying their schoolbags. This pain is related with carrying a schoolbag. The majority of students (53.5percent) felt that their daily pain interferes with their ability to study. In order of severity, the majority of students report having discomfort in their shoulders (82.7percent), lower back (59.9percent), neck (47.0percent), upper back (40.7percent), and upper arm (16.4percent). CONCLUSION: According to the study, there is a link between students' musculoskeletal pain and carrying hefty backpacks or school bags. The shoulders are where musculoskeletal discomfort is most frequently felt. The study supported the findings of the majority of studies cited in the literature that most schoolchildren suffer from musculoskeletal pain because the weight of their backpacks is excessive compared to their size, weight, and age. RECOMMENDATIONS: The study produced a number of recommendations, including that the Department of Basic Education inform teachers, students, parents, guardians, and other key stakeholders about the effects of heavy backpacks or schoolbags on students' musculoskeletal pain. For students' convenience and to lighten the load on their school bags, locker rooms should be available. Teachers, parents, and guardians should also pay attention to the school bags that students are using to make sure that the weight is appropriate for their age and body size. , Thesis (MPA) -- Faculty of Health Sciences, 2022
- Full Text:
- Date Issued: 2022