Symmetry effect of cobalt phthalocyanines on the aluminium corrosion inhibition in hydrochloric acid
- Nnaji, Nnaemeka, Sen, Pinar, Nyokong, Tebello
- Authors: Nnaji, Nnaemeka , Sen, Pinar , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231323 , vital:49877 , xlink:href="https://doi.org/10.1016/j.matlet.2021.130892"
- Description: The aluminium corrosion retardation potentials of phthalocyanine-based dyes, cobalt (II) 2,9,16-tris(4-(tert-butyl)phenoxy)-23-(pyridin-4-yloxy)phthalocyanine (D1) and cobalt (II) 2,9,16,24-tetrakis(4-(tert-butyl)phenoxy)phthalocyanine (D2) in 1 M hydrochloric acid were evaluated. Results from potentiodynamic polarization measurements show that inhibition efficiency increased with inhibitor concentration at 28 °C with values of 91.9 % and 87.0 % values respectively for D1 and D2 at 10 μM.
- Full Text:
- Date Issued: 2022
Symmetry effect of cobalt phthalocyanines on the aluminium corrosion inhibition in hydrochloric acid
- Authors: Nnaji, Nnaemeka , Sen, Pinar , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231323 , vital:49877 , xlink:href="https://doi.org/10.1016/j.matlet.2021.130892"
- Description: The aluminium corrosion retardation potentials of phthalocyanine-based dyes, cobalt (II) 2,9,16-tris(4-(tert-butyl)phenoxy)-23-(pyridin-4-yloxy)phthalocyanine (D1) and cobalt (II) 2,9,16,24-tetrakis(4-(tert-butyl)phenoxy)phthalocyanine (D2) in 1 M hydrochloric acid were evaluated. Results from potentiodynamic polarization measurements show that inhibition efficiency increased with inhibitor concentration at 28 °C with values of 91.9 % and 87.0 % values respectively for D1 and D2 at 10 μM.
- Full Text:
- Date Issued: 2022
Synergistic recognition and electrochemical sensing of 17β-Estradiol using ordered molecularly imprinted polymer-graphene oxide-silver nanoparticles composite films
- Regasa, Melkamu Biyana, Nyokong, Tebello
- Authors: Regasa, Melkamu Biyana , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/295829 , vital:57382 , xlink:href="https://doi.org/10.1016/j.jelechem.2022.116713"
- Description: Synthetic molecularly imprinted polymers (MIPs) based functional materials become the best alternatives to alleviate the stability and cost issues related to biological receptors commonly used in biochemical sensors. To address this demand, we report the development of a highly selective and sensitive MIPs-based electrochemical sensor for the detection of 17β-estradiol (E2). The sensor was prepared based on the MIP-graphene oxide (GO)-silver nanoparticle (AgNP) nanocomposite functional materials electrodeposited on the surface of the glassy carbon electrode (GCE). At first, AgNp formation was facilitated by using ascorbic acid to reduce and stabilize it. A very stable MIP-GO-AgNP sensing layer with multifunctional units were formed using imidazole as a functional monomer (p-type-electron acceptor), GO (n-type-electron donor), and AgNP by using the electrodeposition method. The role of GO in the system is providing additional functional units to bind the template and improve materials morphology while that of AgNPs is acting as a catalyst and charge carrier. The characterization of the sensing materials was done by using Fourier transform infrared, scanning electron microscopy, energy dispersive X-ray spectroscopy, and cyclic voltammetry. After optimization of the essential parameters, the sensor was successfully applied to detect the target analyte using the square wave voltammetric technique. The prepared sensor exhibited a wide linear range of 10 fM-250 nM with the limit of detection and limit of quantification of 3.01 fM and 10.03 fM, respectively. The high percentage recoveries, sensitivity, repeatability, and easy fabrication of the MIP-GO-AgNP materials made the proposed sensor promising for environmental monitoring applications in the future.
- Full Text:
- Date Issued: 2022
- Authors: Regasa, Melkamu Biyana , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/295829 , vital:57382 , xlink:href="https://doi.org/10.1016/j.jelechem.2022.116713"
- Description: Synthetic molecularly imprinted polymers (MIPs) based functional materials become the best alternatives to alleviate the stability and cost issues related to biological receptors commonly used in biochemical sensors. To address this demand, we report the development of a highly selective and sensitive MIPs-based electrochemical sensor for the detection of 17β-estradiol (E2). The sensor was prepared based on the MIP-graphene oxide (GO)-silver nanoparticle (AgNP) nanocomposite functional materials electrodeposited on the surface of the glassy carbon electrode (GCE). At first, AgNp formation was facilitated by using ascorbic acid to reduce and stabilize it. A very stable MIP-GO-AgNP sensing layer with multifunctional units were formed using imidazole as a functional monomer (p-type-electron acceptor), GO (n-type-electron donor), and AgNP by using the electrodeposition method. The role of GO in the system is providing additional functional units to bind the template and improve materials morphology while that of AgNPs is acting as a catalyst and charge carrier. The characterization of the sensing materials was done by using Fourier transform infrared, scanning electron microscopy, energy dispersive X-ray spectroscopy, and cyclic voltammetry. After optimization of the essential parameters, the sensor was successfully applied to detect the target analyte using the square wave voltammetric technique. The prepared sensor exhibited a wide linear range of 10 fM-250 nM with the limit of detection and limit of quantification of 3.01 fM and 10.03 fM, respectively. The high percentage recoveries, sensitivity, repeatability, and easy fabrication of the MIP-GO-AgNP materials made the proposed sensor promising for environmental monitoring applications in the future.
- Full Text:
- Date Issued: 2022
Synthesis and conformational studies of 5-bromo-1-[(N-substituted-carbamoyl) methyl]-7-azabenzimidazoles
- Oluwafemi, Kola A, Klein, Rosalyn, Lobb, Kevin A, Tshiwawa, Tendamudzimu, Isaacs, Michelle, Hoppe, Heinrich C, Kaye, Perry T
- Authors: Oluwafemi, Kola A , Klein, Rosalyn , Lobb, Kevin A , Tshiwawa, Tendamudzimu , Isaacs, Michelle , Hoppe, Heinrich C , Kaye, Perry T
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/452800 , vital:75171 , xlink:href="https://doi.org/10.1016/j.molstruc.2022.133811"
- Description: The Cs2CO3-catalysed condensation of 5-bromo-7-azabenzimidazole with a series of bromomethyl ketones has afforded a small library of ten, novel 5-bromo-1-[(N-substututed-carbamoyl)methyl]-7-azabenzimidazoles. Rotamerism in the products, as evidenced by the splitting of 1H- and 13C-NMR signals, is attributed to hindered internal rotation about the amide N-C(=O) bond, and has been explored using dynamic NMR (DNMR) analysis and computational methods at the GIAO B3LYP/6-311+G(2d,p) level of theory. Coalescence temperatures have been obtained for representative examples and rotational barriers determined experimentally and theoretically. A detailed theoretical analysis has been undertaken to explore conformations which may contribute to the relative populations of the s-cis and s-trans rotamers. The products have also been screened for cytotoxicity and activity against two parasitic protozoan strains (Plasmodium falciparum and Trypanosoma brucei).
- Full Text:
- Date Issued: 2022
- Authors: Oluwafemi, Kola A , Klein, Rosalyn , Lobb, Kevin A , Tshiwawa, Tendamudzimu , Isaacs, Michelle , Hoppe, Heinrich C , Kaye, Perry T
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/452800 , vital:75171 , xlink:href="https://doi.org/10.1016/j.molstruc.2022.133811"
- Description: The Cs2CO3-catalysed condensation of 5-bromo-7-azabenzimidazole with a series of bromomethyl ketones has afforded a small library of ten, novel 5-bromo-1-[(N-substututed-carbamoyl)methyl]-7-azabenzimidazoles. Rotamerism in the products, as evidenced by the splitting of 1H- and 13C-NMR signals, is attributed to hindered internal rotation about the amide N-C(=O) bond, and has been explored using dynamic NMR (DNMR) analysis and computational methods at the GIAO B3LYP/6-311+G(2d,p) level of theory. Coalescence temperatures have been obtained for representative examples and rotational barriers determined experimentally and theoretically. A detailed theoretical analysis has been undertaken to explore conformations which may contribute to the relative populations of the s-cis and s-trans rotamers. The products have also been screened for cytotoxicity and activity against two parasitic protozoan strains (Plasmodium falciparum and Trypanosoma brucei).
- Full Text:
- Date Issued: 2022
Synthesis and in vitro biological studies of ursolic acid-based hybrid compounds
- Authors: Khwaza, Vuyolwethu
- Date: 2022
- Subjects: Herbal medicine , Herbs -- Therapeutic use , Antineoplastic antibiotics
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/27797 , vital:69689
- Description: Ursolic acid UA, a pentacyclic triterpenoid that is commonly found in many medicinal herbs and fruits, has been identified as a potential source of therapeutic agents because of its potent biological effects, which include its potential anticancer and antimicrobial activities. However, its limited solubility, rapid metabolism and poor bioavailability inhibit its clinical applications. Numerous UA derivatives have been prepared over the past years in an effort to mitigate the drawbacks associated with UA, as new chemical entities for the treatment of various infections. There is very little progress in the discovery of efficient UA derivatives. In this study, a class of ester and amide-linked ursolic acid-based hybrid compounds fused with selected pharmaceutical scaffolds were successfully synthesized using amidation and esterification reactions and tested for antibacterial and cytotoxicity activities. Hybridizing UA with other known pharmaceutical scaffolds has the potential of overcoming its drawbacks. FT-IR, Mass Spectroscopy, and 1H13C-NMR spectroscopy were used to confirm the structures of the synthesized hybrid compounds. Among the tested ester-linked hybrid compounds in Chapter three, compounds 3.14-3.19,3.21, 3.34, 3.31, and 3.30 demonstrated significant antibacterial activities against some tested bacteria, with MIC values of 15.625 μgml. Furthermore, the in vitro cytotoxicity of these hybrids was determined using the MTT assay against three human tumor cell lines MCF7, MDA-MB-231, and HeLa cells. Compounds 3.19 and 3.34 were found to have better cytotoxic activity when compared to ursolic acid, with IC50 values of 46.99 and 48.18 μg ml respectively. Both compounds revealed more promising docking results, presenting favourable binding interactions as well as better docking energy against the MCF 7 protein target compared to the parent compound ursolic acid. In Chapter Four, among the tested amide-linked hybrid compounds, Compounds 4.17 and 4.24 demonstrated significant antibacterial activity against the majority of bacterial strains with MIC values of 15.625 gml. Compound 4.24 exhibited a MIC value of 15.625gmL against BS, SA, PV, KO, PM, and EC. Compound 4.23 was more cytotoxic to HeLa cells than ursolic acid. Furthermore, molecular docking calculations revealed that compound 4.16 strongly binds to the protein epidermal growth factor receptor while e compounds 4.17 and 4.24 showed a strong binding affinity for the methionyl-tRNA synthetase. In both cases, the hybrid compounds showed better conformational fittings in the active site of the targeted proteins as compared to the parent ursolic acid. , Thesis (MSc) -- Faculty of Science and Agriculture, 2022
- Full Text:
- Date Issued: 2022
- Authors: Khwaza, Vuyolwethu
- Date: 2022
- Subjects: Herbal medicine , Herbs -- Therapeutic use , Antineoplastic antibiotics
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/27797 , vital:69689
- Description: Ursolic acid UA, a pentacyclic triterpenoid that is commonly found in many medicinal herbs and fruits, has been identified as a potential source of therapeutic agents because of its potent biological effects, which include its potential anticancer and antimicrobial activities. However, its limited solubility, rapid metabolism and poor bioavailability inhibit its clinical applications. Numerous UA derivatives have been prepared over the past years in an effort to mitigate the drawbacks associated with UA, as new chemical entities for the treatment of various infections. There is very little progress in the discovery of efficient UA derivatives. In this study, a class of ester and amide-linked ursolic acid-based hybrid compounds fused with selected pharmaceutical scaffolds were successfully synthesized using amidation and esterification reactions and tested for antibacterial and cytotoxicity activities. Hybridizing UA with other known pharmaceutical scaffolds has the potential of overcoming its drawbacks. FT-IR, Mass Spectroscopy, and 1H13C-NMR spectroscopy were used to confirm the structures of the synthesized hybrid compounds. Among the tested ester-linked hybrid compounds in Chapter three, compounds 3.14-3.19,3.21, 3.34, 3.31, and 3.30 demonstrated significant antibacterial activities against some tested bacteria, with MIC values of 15.625 μgml. Furthermore, the in vitro cytotoxicity of these hybrids was determined using the MTT assay against three human tumor cell lines MCF7, MDA-MB-231, and HeLa cells. Compounds 3.19 and 3.34 were found to have better cytotoxic activity when compared to ursolic acid, with IC50 values of 46.99 and 48.18 μg ml respectively. Both compounds revealed more promising docking results, presenting favourable binding interactions as well as better docking energy against the MCF 7 protein target compared to the parent compound ursolic acid. In Chapter Four, among the tested amide-linked hybrid compounds, Compounds 4.17 and 4.24 demonstrated significant antibacterial activity against the majority of bacterial strains with MIC values of 15.625 gml. Compound 4.24 exhibited a MIC value of 15.625gmL against BS, SA, PV, KO, PM, and EC. Compound 4.23 was more cytotoxic to HeLa cells than ursolic acid. Furthermore, molecular docking calculations revealed that compound 4.16 strongly binds to the protein epidermal growth factor receptor while e compounds 4.17 and 4.24 showed a strong binding affinity for the methionyl-tRNA synthetase. In both cases, the hybrid compounds showed better conformational fittings in the active site of the targeted proteins as compared to the parent ursolic acid. , Thesis (MSc) -- Faculty of Science and Agriculture, 2022
- Full Text:
- Date Issued: 2022
Synthesis of 2, 3-dihydroxy-3-(N-substituted carbamoyl) propylphosphonic acid derivatives as hybrid DOXP-fosmidomycin analogues
- Mutorwa, Marius K, Lobb, Kevin A, Klein, Rosalyn, Blatch, Gregory L, Kaye, Perry T
- Authors: Mutorwa, Marius K , Lobb, Kevin A , Klein, Rosalyn , Blatch, Gregory L , Kaye, Perry T
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/453212 , vital:75231 , xlink:href="https://doi.org/10.1016/j.molstruc.2022.132453"
- Description: A six-step synthetic pathway has been established to access a series of racemic 2,3-dihydroxy-3-(Nsubstituted carbamoyl)propylphosphonic acid derivatives, designed to contain structural features common to both the natural substrate 1-deoxy-D-xylulose 5-phosphate (DOXP) of the Plasmodium falciparum (Pf) DXR enzyme and its known inhibitor, fosmidomycin. Positive STD-NMR and in silico docking data obtained for some of the compounds indicate their capacity to bind to the analogous E.coli DXR enzyme.
- Full Text:
- Date Issued: 2022
- Authors: Mutorwa, Marius K , Lobb, Kevin A , Klein, Rosalyn , Blatch, Gregory L , Kaye, Perry T
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/453212 , vital:75231 , xlink:href="https://doi.org/10.1016/j.molstruc.2022.132453"
- Description: A six-step synthetic pathway has been established to access a series of racemic 2,3-dihydroxy-3-(Nsubstituted carbamoyl)propylphosphonic acid derivatives, designed to contain structural features common to both the natural substrate 1-deoxy-D-xylulose 5-phosphate (DOXP) of the Plasmodium falciparum (Pf) DXR enzyme and its known inhibitor, fosmidomycin. Positive STD-NMR and in silico docking data obtained for some of the compounds indicate their capacity to bind to the analogous E.coli DXR enzyme.
- Full Text:
- Date Issued: 2022
Synthesis, stereochemistry and in vitro STD NMR and in silico HIV-1 PR enzyme-binding potential of MBH-derived inhibitors
- Tukulula, Matshawandile, Olasupo, Idris A, Mugumbate, Grace C, Lobb, Kevin A, Klein, Rosalyn, Sayed, Yasien, Tshiwawa, Tendamudzimu, Kaye, Perry T
- Authors: Tukulula, Matshawandile , Olasupo, Idris A , Mugumbate, Grace C , Lobb, Kevin A , Klein, Rosalyn , Sayed, Yasien , Tshiwawa, Tendamudzimu , Kaye, Perry T
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/452813 , vital:75172 , xlink:href="https://doi.org/10.1016/j.molstruc.2022.133716"
- Description: Aza-Michael reactions of a pyridine-3-carbaldehyde-derived Morita-Baylis-Hillman (MBH) adduct with various amines have afforded a series of 10 diastereomeric products, stereochemical analysis of which has been achieved using a combination of NMR (1D, 2D and NOESY) and computer modelling methods. Saturation Transfer Difference (STD) 1H NMR spectroscopy and in silico molecular docking studies have been used to explore the HIV-1 protease sub-type C enzyme binding potential of these compounds in five different HIV-1 PR enzyme receptors.
- Full Text:
- Date Issued: 2022
- Authors: Tukulula, Matshawandile , Olasupo, Idris A , Mugumbate, Grace C , Lobb, Kevin A , Klein, Rosalyn , Sayed, Yasien , Tshiwawa, Tendamudzimu , Kaye, Perry T
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/452813 , vital:75172 , xlink:href="https://doi.org/10.1016/j.molstruc.2022.133716"
- Description: Aza-Michael reactions of a pyridine-3-carbaldehyde-derived Morita-Baylis-Hillman (MBH) adduct with various amines have afforded a series of 10 diastereomeric products, stereochemical analysis of which has been achieved using a combination of NMR (1D, 2D and NOESY) and computer modelling methods. Saturation Transfer Difference (STD) 1H NMR spectroscopy and in silico molecular docking studies have been used to explore the HIV-1 protease sub-type C enzyme binding potential of these compounds in five different HIV-1 PR enzyme receptors.
- Full Text:
- Date Issued: 2022
Systematic review of genome-wide association studies of anxiety disorders and neuroticism
- Van Der Walt, Kristien, Campbell, Megan, Stein, Dan J, Dalvie, Shareefa
- Authors: Van Der Walt, Kristien , Campbell, Megan , Stein, Dan J , Dalvie, Shareefa
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/302532 , vital:58205 , xlink:href="https://doi.org//10.1080/15622975.2022.2099970"
- Description: Objectives: To summarise SNP associations identified by genome-wide association studies (GWASs) of anxiety disorders and neuroticism; to appraise the quality of individual studies, and to assess the ancestral diversity of study participants. Methods: We searched PubMed, Scopus, PsychInfo and PubPsych for GWASs of anxiety disorders, non-diagnostic traits (such as anxiety sensitivity), and neuroticism, and extracted all SNPs that surpassed genome-wide significance. We graded study quality using Q-genie scores and reviewed the ancestral diversity of included participants. Results: 32 studies met our inclusion criteria. A total of 563 independent significant variants were identified, of which 29 were replicated nominally in independent samples, and 3 were replicated significantly. The studies had good global quality, but many smaller studies were underpowered. Phenotypic heterogeneity for anxiety (and less so for neuroticism) seemed to reflect the complexity of capturing this trait. Ancestral diversity was poor, with 70% of studies including only populations of European ancestry. Conclusion: The functionality of genes identified by GWASs of anxiety and neuroticism deserves further investigation. Future GWASs should have larger sample sizes, more rigorous phenotyping and include more ancestrally diverse population groups.
- Full Text:
- Date Issued: 2022
- Authors: Van Der Walt, Kristien , Campbell, Megan , Stein, Dan J , Dalvie, Shareefa
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/302532 , vital:58205 , xlink:href="https://doi.org//10.1080/15622975.2022.2099970"
- Description: Objectives: To summarise SNP associations identified by genome-wide association studies (GWASs) of anxiety disorders and neuroticism; to appraise the quality of individual studies, and to assess the ancestral diversity of study participants. Methods: We searched PubMed, Scopus, PsychInfo and PubPsych for GWASs of anxiety disorders, non-diagnostic traits (such as anxiety sensitivity), and neuroticism, and extracted all SNPs that surpassed genome-wide significance. We graded study quality using Q-genie scores and reviewed the ancestral diversity of included participants. Results: 32 studies met our inclusion criteria. A total of 563 independent significant variants were identified, of which 29 were replicated nominally in independent samples, and 3 were replicated significantly. The studies had good global quality, but many smaller studies were underpowered. Phenotypic heterogeneity for anxiety (and less so for neuroticism) seemed to reflect the complexity of capturing this trait. Ancestral diversity was poor, with 70% of studies including only populations of European ancestry. Conclusion: The functionality of genes identified by GWASs of anxiety and neuroticism deserves further investigation. Future GWASs should have larger sample sizes, more rigorous phenotyping and include more ancestrally diverse population groups.
- Full Text:
- Date Issued: 2022
Systematic revision of Afrogecko ansorgii (Boulenger, 1907)(Sauria: Gekkonidae) from western Angola
- Lobón-Rovira, Javier, Conradie, Werner C, Pinto, Pedro V, Keates, Chad, Edwards, Shelley, du Plessis, Anton, Branch, William R
- Authors: Lobón-Rovira, Javier , Conradie, Werner C , Pinto, Pedro V , Keates, Chad , Edwards, Shelley , du Plessis, Anton , Branch, William R
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/461550 , vital:76212 , xlink:href="https://doi.org/10.11646/zootaxa.5124.4.1"
- Description: Here we provide the first phylogenetic analysis that include Afrogecko ansorgii and a detailed morphological comparison with other species of leaf-toed geckos. For this purpose, we used two mitochondrial (16S, ND2) and four nuclear (RAG1, RAG2, CMOS, PDC) genes to produce a robust phylogenetic reconstruction. This allowed us to show that A. ansorgii is not related as previously believed to circum-Indian Ocean leaf-toed geckos and is rather more closely related to other Malagasy leaf-toed geckos. Additionally, we explore and compare osteological variation in A. ansorgii skulls through High Resolution X-ray Computed Tomography with previously published material. This allowed us to describe herein a new genus, Bauerius gen. nov., and additionally provide a detailed redescription of the species (including the first description of male material), supplementing the limited original description and type series, which consisted of only two females.
- Full Text:
- Date Issued: 2022
- Authors: Lobón-Rovira, Javier , Conradie, Werner C , Pinto, Pedro V , Keates, Chad , Edwards, Shelley , du Plessis, Anton , Branch, William R
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/461550 , vital:76212 , xlink:href="https://doi.org/10.11646/zootaxa.5124.4.1"
- Description: Here we provide the first phylogenetic analysis that include Afrogecko ansorgii and a detailed morphological comparison with other species of leaf-toed geckos. For this purpose, we used two mitochondrial (16S, ND2) and four nuclear (RAG1, RAG2, CMOS, PDC) genes to produce a robust phylogenetic reconstruction. This allowed us to show that A. ansorgii is not related as previously believed to circum-Indian Ocean leaf-toed geckos and is rather more closely related to other Malagasy leaf-toed geckos. Additionally, we explore and compare osteological variation in A. ansorgii skulls through High Resolution X-ray Computed Tomography with previously published material. This allowed us to describe herein a new genus, Bauerius gen. nov., and additionally provide a detailed redescription of the species (including the first description of male material), supplementing the limited original description and type series, which consisted of only two females.
- Full Text:
- Date Issued: 2022
Technology Adoption Readiness in Disadvantaged Universities during COVID 19 Pandemic in South Africa
- Aruleba, Kehinde., Jere, Nobert., Matarirano, Obert.
- Authors: Aruleba, Kehinde. , Jere, Nobert. , Matarirano, Obert.
- Date: 2022
- Subjects: Covid 19 Readiness for school Web-based instruction Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6544 , vital:46489 , xlink:href="https://doi.org/10.5430/ijhe.v11n2p172"
- Description: The Covid 19 pandemic has affected hundreds of million lives and taken over four million lives to date. As a result, governments and policymakers see the need for emergency action to reduce the spread of the virus. In an attempt to contain the virus, governments and policymakers worldwide introduced a different range of prote ction measures and interventions to change their citizen's behaviours , primarily through social distancing, interprovince lockdown, stay at home strategies, and quarantines. The different lockdown measures have created unique and challenging conditions wit h no documented equivalent in the education sector. A significant effect was that many Higher Education institutions worldwide were not ready to switch to online teaching and learning when the governments announced the sudden lockdown. This study discusses the effect s of the Covid 19 pandemic on South Africa Higher Education Institution s , focusing on the historically disadvantaged universities. The study went further to evaluate the readiness of lecturers from selected disadvantaged universities to adopting online teaching and learning by applying the Technology Readiness Acceptance Model (TRAM). Quantitative data was collected through an online questionnaire. Results show that the higher the average of optimism and innovativeness among the respondents' poin t towards the readiness of adopting technology. On the other hand, higher the average insecurity and discomfort show the uneasiness of adopting technologies by the respondents.
- Full Text:
- Date Issued: 2022
Technology Adoption Readiness in Disadvantaged Universities during COVID 19 Pandemic in South Africa
- Authors: Aruleba, Kehinde. , Jere, Nobert. , Matarirano, Obert.
- Date: 2022
- Subjects: Covid 19 Readiness for school Web-based instruction Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6544 , vital:46489 , xlink:href="https://doi.org/10.5430/ijhe.v11n2p172"
- Description: The Covid 19 pandemic has affected hundreds of million lives and taken over four million lives to date. As a result, governments and policymakers see the need for emergency action to reduce the spread of the virus. In an attempt to contain the virus, governments and policymakers worldwide introduced a different range of prote ction measures and interventions to change their citizen's behaviours , primarily through social distancing, interprovince lockdown, stay at home strategies, and quarantines. The different lockdown measures have created unique and challenging conditions wit h no documented equivalent in the education sector. A significant effect was that many Higher Education institutions worldwide were not ready to switch to online teaching and learning when the governments announced the sudden lockdown. This study discusses the effect s of the Covid 19 pandemic on South Africa Higher Education Institution s , focusing on the historically disadvantaged universities. The study went further to evaluate the readiness of lecturers from selected disadvantaged universities to adopting online teaching and learning by applying the Technology Readiness Acceptance Model (TRAM). Quantitative data was collected through an online questionnaire. Results show that the higher the average of optimism and innovativeness among the respondents' poin t towards the readiness of adopting technology. On the other hand, higher the average insecurity and discomfort show the uneasiness of adopting technologies by the respondents.
- Full Text:
- Date Issued: 2022
The (Slow) Urgency of Socio-cological Justice in ESE–Listening to Children in Marginalized Positions in ESE
- Jørgensen, Nanna J, James, Anna
- Authors: Jørgensen, Nanna J , James, Anna
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/437526 , vital:73391 , ISBN
- Description: As a contribution to discussions about how ESE research respond to increasing urgency and climate emergencies, this essay discusses the relation between education and the pursuit of societal transformation with a view to questions of socio-ecological justice. Our research interest centers on young children’s participation and voice, on the inequalities which constitute barriers to this participation, and on the potentials of a more fine-tuned pedagogy which listens to children’s voices and their relations with the non-human environment in our research practices. This listening is a radical process of unlearning and rethinking ‘urgency’. The essay is based on an ongoing dialogue about how research on sustainability education might respond to the voices of children in marginalized positions across two very different geographical and socio-cultural settings–the Danish welfare state and post-apartheid South Africa (see James and Jørgensen, forthcoming). Here we draw attention to the dangers of assumptions underlying urgency (dualism and instrumentalism) and the voices of young children in research as a practice that resists these dangers.
- Full Text:
- Date Issued: 2022
- Authors: Jørgensen, Nanna J , James, Anna
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/437526 , vital:73391 , ISBN
- Description: As a contribution to discussions about how ESE research respond to increasing urgency and climate emergencies, this essay discusses the relation between education and the pursuit of societal transformation with a view to questions of socio-ecological justice. Our research interest centers on young children’s participation and voice, on the inequalities which constitute barriers to this participation, and on the potentials of a more fine-tuned pedagogy which listens to children’s voices and their relations with the non-human environment in our research practices. This listening is a radical process of unlearning and rethinking ‘urgency’. The essay is based on an ongoing dialogue about how research on sustainability education might respond to the voices of children in marginalized positions across two very different geographical and socio-cultural settings–the Danish welfare state and post-apartheid South Africa (see James and Jørgensen, forthcoming). Here we draw attention to the dangers of assumptions underlying urgency (dualism and instrumentalism) and the voices of young children in research as a practice that resists these dangers.
- Full Text:
- Date Issued: 2022
The contribution of wild palms to the livelihoods and diversification of rural households in southern Mozambique
- King, Angelina R, Shackleton, Charlie M
- Authors: King, Angelina R , Shackleton, Charlie M
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/399846 , vital:69563 , xlink:href="https://doi.org/10.1016/j.forpol.2022.102793"
- Description: In most low-income countries, rural households combine a range of economic activities to generate income, achieve food and nutritional security and fulfill other livelihood objectives, including: small-scale farming, fishing, hunting, livestock and timber production, and non-timber forest products gathering, as well as off-farm activities such as wage labour and informal trading. This work examines the role of diversification, including palm products income, on rural livelihoods in the Zitundo area, southern Mozambique. Seven livelihood strategies were identified, with every strategy combining cash income from several sources. Most households adopt a wage-based strategy to some degree, although this strategy shows low potential for reducing poverty in the area. Households adopting a palm-based strategy show between 23% and 60% lower poverty incidence than those adopting alternatives strategies. Yet, a palm-based livelihood strategy was adopted by only 11% of households. Traders of palm products earn approximately double the annual income and per capita income than non-traders. Village of residency and some household socio-economic and demographic characteristics correlate with a households' choice of livelihood strategy and palm income dependency. The adherence of many households to a less remunerative wage strategy indicates other factors also influence the choice of livelihood strategies. The study shows that future development plans and policy interventions to mitigate poverty in the area should go beyond the usual agricultural sector and recognize the role of non-timber forest products, especially palm products, for people's livelihoods and poverty alleviation.
- Full Text:
- Date Issued: 2022
- Authors: King, Angelina R , Shackleton, Charlie M
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/399846 , vital:69563 , xlink:href="https://doi.org/10.1016/j.forpol.2022.102793"
- Description: In most low-income countries, rural households combine a range of economic activities to generate income, achieve food and nutritional security and fulfill other livelihood objectives, including: small-scale farming, fishing, hunting, livestock and timber production, and non-timber forest products gathering, as well as off-farm activities such as wage labour and informal trading. This work examines the role of diversification, including palm products income, on rural livelihoods in the Zitundo area, southern Mozambique. Seven livelihood strategies were identified, with every strategy combining cash income from several sources. Most households adopt a wage-based strategy to some degree, although this strategy shows low potential for reducing poverty in the area. Households adopting a palm-based strategy show between 23% and 60% lower poverty incidence than those adopting alternatives strategies. Yet, a palm-based livelihood strategy was adopted by only 11% of households. Traders of palm products earn approximately double the annual income and per capita income than non-traders. Village of residency and some household socio-economic and demographic characteristics correlate with a households' choice of livelihood strategy and palm income dependency. The adherence of many households to a less remunerative wage strategy indicates other factors also influence the choice of livelihood strategies. The study shows that future development plans and policy interventions to mitigate poverty in the area should go beyond the usual agricultural sector and recognize the role of non-timber forest products, especially palm products, for people's livelihoods and poverty alleviation.
- Full Text:
- Date Issued: 2022
The double burden of treating traumatic stress in low-resource communities: experiences and perspectives of non-specialist health workers in South Africa
- Booysen, Duane D, Kagee, Ashraf
- Authors: Booysen, Duane D , Kagee, Ashraf
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/454132 , vital:75312 , xlink:href="https://doi.org/10.1177/0081246320984051 "
- Description: Considering the global trend towards the dissemination and implementation of trauma-focused treatments in the majority of the world, it is imperative to ascertain the contextual factors which affect the treatment of traumatic stress, especially in low- and middle-income countries characterised by ongoing adversity such as poverty and increased levels of trauma exposure. We explored the experiences of non-specialist health workers whose work involved providing trauma-focused services in low-resource communities in South Africa. Participants (n = 18) worked at four non-governmental organisations in the Eastern Cape and Western Cape of South Africa. Semi-structured individual interviews were conducted and analysed using a phenomenologically informed thematic analysis. Two superordinate themes were identified, namely, adjusting to trauma-focused work and trauma in the social context. Five themes that made up the superordinate themes were Encountering Trauma Narratives, Support and Resilience, Going the Extra Mile, Helplessness, and Social Factors. The findings are not only in keeping with the psychological risks of trauma-focused work (e.g., vicarious traumatisation) but also highlighting the impact of the social context on the provision of trauma-focused work. Participants reported experiencing an added burden of helplessness due to social factors, such as poverty and high levels of trauma exposure, which affect the process of treating traumatic stress in low-resource settings. We discuss how these findings can contribute to efforts to implement trauma-focused services in low- and middle-income countries.
- Full Text:
- Date Issued: 2022
- Authors: Booysen, Duane D , Kagee, Ashraf
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/454132 , vital:75312 , xlink:href="https://doi.org/10.1177/0081246320984051 "
- Description: Considering the global trend towards the dissemination and implementation of trauma-focused treatments in the majority of the world, it is imperative to ascertain the contextual factors which affect the treatment of traumatic stress, especially in low- and middle-income countries characterised by ongoing adversity such as poverty and increased levels of trauma exposure. We explored the experiences of non-specialist health workers whose work involved providing trauma-focused services in low-resource communities in South Africa. Participants (n = 18) worked at four non-governmental organisations in the Eastern Cape and Western Cape of South Africa. Semi-structured individual interviews were conducted and analysed using a phenomenologically informed thematic analysis. Two superordinate themes were identified, namely, adjusting to trauma-focused work and trauma in the social context. Five themes that made up the superordinate themes were Encountering Trauma Narratives, Support and Resilience, Going the Extra Mile, Helplessness, and Social Factors. The findings are not only in keeping with the psychological risks of trauma-focused work (e.g., vicarious traumatisation) but also highlighting the impact of the social context on the provision of trauma-focused work. Participants reported experiencing an added burden of helplessness due to social factors, such as poverty and high levels of trauma exposure, which affect the process of treating traumatic stress in low-resource settings. We discuss how these findings can contribute to efforts to implement trauma-focused services in low- and middle-income countries.
- Full Text:
- Date Issued: 2022
The effect of charge on Zn tetra morpholine porphyrin conjugated to folic acid-nitrogen doped graphene quantum dots for photodynamic therapy studies
- Magaela, N Bridged, Matshitse, Refilwe, Nyokong, Tebello
- Authors: Magaela, N Bridged , Matshitse, Refilwe , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/295840 , vital:57383 , xlink:href="https://doi.org/10.1016/j.pdpdt.2022.102898"
- Description: Zinc tetra morpholine porphyrin (complex 2), and its quaternized derivative (complex 3) were synthesized and conjugated to folic acid decorated nitrogen doped graphene quantum dots (FA-NGQDs) through π−π stacking to study their photodynamic therapy (PDT) efficacy. Photophysiochemical properties of complexes 2, 3, and their conjugates (2-FA-NGQDs, 3-FA-NGQDs) were studied. It was found that complex 3 had higher ϕΔ of 0.56 compared to complex 2 with ϕΔ of 0.24, and respective composites: 3-FA-NGQDs had higher ϕΔ compared to 2-FA-NGQDs. The PDT studies were conducted for nanoparticles (FA-NGQDs), complexes (2, 3), and respective composites (2-FA-NGQDs, and 3-FA-NGQDs) using MCF-7 breast cancer cell. Dark toxicity of all compounds was above 90% which is negligible. At a highest concentration of 40 µg/mL, 3-FA-NGQDs gave the lowest cell viability of 28% compared to all other conjugates and porphyrins alone.
- Full Text:
- Date Issued: 2022
- Authors: Magaela, N Bridged , Matshitse, Refilwe , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/295840 , vital:57383 , xlink:href="https://doi.org/10.1016/j.pdpdt.2022.102898"
- Description: Zinc tetra morpholine porphyrin (complex 2), and its quaternized derivative (complex 3) were synthesized and conjugated to folic acid decorated nitrogen doped graphene quantum dots (FA-NGQDs) through π−π stacking to study their photodynamic therapy (PDT) efficacy. Photophysiochemical properties of complexes 2, 3, and their conjugates (2-FA-NGQDs, 3-FA-NGQDs) were studied. It was found that complex 3 had higher ϕΔ of 0.56 compared to complex 2 with ϕΔ of 0.24, and respective composites: 3-FA-NGQDs had higher ϕΔ compared to 2-FA-NGQDs. The PDT studies were conducted for nanoparticles (FA-NGQDs), complexes (2, 3), and respective composites (2-FA-NGQDs, and 3-FA-NGQDs) using MCF-7 breast cancer cell. Dark toxicity of all compounds was above 90% which is negligible. At a highest concentration of 40 µg/mL, 3-FA-NGQDs gave the lowest cell viability of 28% compared to all other conjugates and porphyrins alone.
- Full Text:
- Date Issued: 2022
The Electrocatalytic Detection of Nitrite Using Manganese Schiff Base Phthalocyanine Complexes
- Ndebele, Nobuhle, Nyokong, Tebello
- Authors: Ndebele, Nobuhle , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/295856 , vital:57385 , xlink:href="https://doi.org/10.1007/s12678-022-00752-4"
- Description: This work investigates the use of manganese phthalocyanines (MnPcs) in the electrochemical detection of nitrite. These are two Schiff base derivatives: tetrakis 4-(4-thio-thiophene-2-ylmethanamino) phthalocyaninato Mn(III)Cl (2) and tetrakis 4-(3-(pyrrolidine-1-yl)propan-1-amino)phthalocyaninato Mn(III)Cl (3) and one aldehyde: tetrakis(4-formylphenoxy)phthalocyaninato Mn(III)Cl (1). The MnPc complexes were adsorbed onto the glassy carbon electrode surface using the drop-dry method and used as electrocatalysts to detect nitrite. Nitrite oxidation peak potentials obtained using cyclic voltammetry ranged between 0.70 and 0.84 V. Detection limits as low as 0.16 µM and sensitivity values as high as 276 µMmM−1 were obtained through the use of chronoamperometry. The Schiff base MnPcs 2 and 3 exhibited better nitrite detection properties (in terms of limit of detection and sensitivity) than their aldehyde precursor (1).
- Full Text:
- Date Issued: 2022
- Authors: Ndebele, Nobuhle , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/295856 , vital:57385 , xlink:href="https://doi.org/10.1007/s12678-022-00752-4"
- Description: This work investigates the use of manganese phthalocyanines (MnPcs) in the electrochemical detection of nitrite. These are two Schiff base derivatives: tetrakis 4-(4-thio-thiophene-2-ylmethanamino) phthalocyaninato Mn(III)Cl (2) and tetrakis 4-(3-(pyrrolidine-1-yl)propan-1-amino)phthalocyaninato Mn(III)Cl (3) and one aldehyde: tetrakis(4-formylphenoxy)phthalocyaninato Mn(III)Cl (1). The MnPc complexes were adsorbed onto the glassy carbon electrode surface using the drop-dry method and used as electrocatalysts to detect nitrite. Nitrite oxidation peak potentials obtained using cyclic voltammetry ranged between 0.70 and 0.84 V. Detection limits as low as 0.16 µM and sensitivity values as high as 276 µMmM−1 were obtained through the use of chronoamperometry. The Schiff base MnPcs 2 and 3 exhibited better nitrite detection properties (in terms of limit of detection and sensitivity) than their aldehyde precursor (1).
- Full Text:
- Date Issued: 2022
The emergence of isiZulu in Skeem Saam (2011)
- Authors: Aiseng, Kealeboga
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/277956 , vital:55335 , xlink:href="https://doi.org/10.1080/13504630.2022.2063115"
- Description: This study aims to investigate how an ecological understanding of polyglossia is used in the South African Broadcasting Corporation’s (SABC) television channel, SABC 1 to maintain and create ethnolinguistic dominance. Key arguments this study will make are: (1) polyglossia is a language ideology masquerading as ethnolinguistic pluralism, (2) there is a loss of ethnolinguistic pluralism in SABC 1 because of the polyglot culture and its transmissions, (3) isiZulu is emerging as a language and cultural flare of the channel. This paper concluded that isiZulu’s presence is rising in a soap initially meant to be a Sepedi show. And this has negative consequences for language equality in the SABC.
- Full Text:
- Date Issued: 2022
- Authors: Aiseng, Kealeboga
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/277956 , vital:55335 , xlink:href="https://doi.org/10.1080/13504630.2022.2063115"
- Description: This study aims to investigate how an ecological understanding of polyglossia is used in the South African Broadcasting Corporation’s (SABC) television channel, SABC 1 to maintain and create ethnolinguistic dominance. Key arguments this study will make are: (1) polyglossia is a language ideology masquerading as ethnolinguistic pluralism, (2) there is a loss of ethnolinguistic pluralism in SABC 1 because of the polyglot culture and its transmissions, (3) isiZulu is emerging as a language and cultural flare of the channel. This paper concluded that isiZulu’s presence is rising in a soap initially meant to be a Sepedi show. And this has negative consequences for language equality in the SABC.
- Full Text:
- Date Issued: 2022
The emergence of isiZulu in Skeem Saam (2011) sociolinguistics: factors and the politics of the ‘loss of ethnolinguistic pluralism’at the SABC 1
- Authors: Aiseng, Kealeboga
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/455285 , vital:75418 , https://doi.org/10.1080/13504630.2022.2063115
- Description: This study aims to investigate how an ecological understanding of pol-yglossia is used in the South African Broadcasting Corporation’s (SABC) television channel, SABC 1 to maintain and create ethnolinguis-tic dominance. Key arguments this study will make are: (1) polyglossia is a language ideology masquerading as ethnolinguistic pluralism, (2) there is a loss of ethnolinguistic pluralism in SABC 1 because of the polyglot culture and its transmissions, (3) isiZulu is emerging as a lan-guage and cultural flare of the channel. This paper concluded that isi-Zulu’s presence is rising in a soap initially meant to be a Sepedi show. And this has negative consequences for language equality in the SABC.
- Full Text:
- Date Issued: 2022
- Authors: Aiseng, Kealeboga
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/455285 , vital:75418 , https://doi.org/10.1080/13504630.2022.2063115
- Description: This study aims to investigate how an ecological understanding of pol-yglossia is used in the South African Broadcasting Corporation’s (SABC) television channel, SABC 1 to maintain and create ethnolinguis-tic dominance. Key arguments this study will make are: (1) polyglossia is a language ideology masquerading as ethnolinguistic pluralism, (2) there is a loss of ethnolinguistic pluralism in SABC 1 because of the polyglot culture and its transmissions, (3) isiZulu is emerging as a lan-guage and cultural flare of the channel. This paper concluded that isi-Zulu’s presence is rising in a soap initially meant to be a Sepedi show. And this has negative consequences for language equality in the SABC.
- Full Text:
- Date Issued: 2022
The experiences of clinical psychologists in treating traumatic stress at a tertiary psychiatric hospital in the Eastern Cape: A qualitative study
- Munishvaran, Kuriesha, Booysen, Duane D
- Authors: Munishvaran, Kuriesha , Booysen, Duane D
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/454158 , vital:75314 , xlink:href="https://www.ajol.info/index.php/sajpsyc/article/view/241251"
- Description: Background: Qualitative data on the experiences of treating post-traumatic stress disorder (PTSD) in a psychiatric setting in a low-resource context is sparse. Aim: The authors aimed to explore the lived experiences of clinical psychologists who treat patients who are either trauma survivors or perpetrators in a psychiatric hospital. Setting: A public psychiatric hospital in the Eastern Cape, South Africa.
- Full Text:
- Date Issued: 2022
- Authors: Munishvaran, Kuriesha , Booysen, Duane D
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/454158 , vital:75314 , xlink:href="https://www.ajol.info/index.php/sajpsyc/article/view/241251"
- Description: Background: Qualitative data on the experiences of treating post-traumatic stress disorder (PTSD) in a psychiatric setting in a low-resource context is sparse. Aim: The authors aimed to explore the lived experiences of clinical psychologists who treat patients who are either trauma survivors or perpetrators in a psychiatric hospital. Setting: A public psychiatric hospital in the Eastern Cape, South Africa.
- Full Text:
- Date Issued: 2022
The extent and impact of variation in ADME genes in sub-Saharan African populations
- da Rocha, Jorge E B, Othman, Houcemeddine, Botha, Gerrit, Cottino, Laura, Twesigomwe, David, Ahmed, Samah, Drögemöller, Britt I, Fadlelmola, Faisal M, Machanick, Philip, Mbiyavanga, Mamana, Panji, Sumir, Wright, Galen E B, Adebamowo, Clement, Matshaba, Mogomotsi, Ramsay, Michéle, Simo, Gustave, Simuunza, Martin C, Tiemessen, Caroline T, Baldwin, Sandra, Chiano, Mathias, Cox, Charles, Gross, Annette S, Thomas, Pamela, Gamo, Francisco-Javier, Scott Hazelhurst
- Authors: da Rocha, Jorge E B , Othman, Houcemeddine , Botha, Gerrit , Cottino, Laura , Twesigomwe, David , Ahmed, Samah , Drögemöller, Britt I , Fadlelmola, Faisal M , Machanick, Philip , Mbiyavanga, Mamana , Panji, Sumir , Wright, Galen E B , Adebamowo, Clement , Matshaba, Mogomotsi , Ramsay, Michéle , Simo, Gustave , Simuunza, Martin C , Tiemessen, Caroline T , Baldwin, Sandra , Chiano, Mathias , Cox, Charles , Gross, Annette S , Thomas, Pamela , Gamo, Francisco-Javier , Scott Hazelhurst
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/439202 , vital:73555 , https://homes.cs.ru.ac.za/philip/Courses/CSHonsArch/HonsArchNotes2022.pdf
- Description: Investigating variation in genes involved in the absorption, distribution, metabolism, and excretion (ADME) of drugs are key to characterizing pharmacogenomic (PGx) relationships. ADME gene variation is relatively well characterized in European and Asian populations, but data from African populations are under-studied—which has implications for drug safety and effective use in Africa.
- Full Text:
- Date Issued: 2022
- Authors: da Rocha, Jorge E B , Othman, Houcemeddine , Botha, Gerrit , Cottino, Laura , Twesigomwe, David , Ahmed, Samah , Drögemöller, Britt I , Fadlelmola, Faisal M , Machanick, Philip , Mbiyavanga, Mamana , Panji, Sumir , Wright, Galen E B , Adebamowo, Clement , Matshaba, Mogomotsi , Ramsay, Michéle , Simo, Gustave , Simuunza, Martin C , Tiemessen, Caroline T , Baldwin, Sandra , Chiano, Mathias , Cox, Charles , Gross, Annette S , Thomas, Pamela , Gamo, Francisco-Javier , Scott Hazelhurst
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/439202 , vital:73555 , https://homes.cs.ru.ac.za/philip/Courses/CSHonsArch/HonsArchNotes2022.pdf
- Description: Investigating variation in genes involved in the absorption, distribution, metabolism, and excretion (ADME) of drugs are key to characterizing pharmacogenomic (PGx) relationships. ADME gene variation is relatively well characterized in European and Asian populations, but data from African populations are under-studied—which has implications for drug safety and effective use in Africa.
- Full Text:
- Date Issued: 2022
The first ‘Grylloblattida’of the family Liomopteridae from the Middle Permian in the Onder Karoo, South Africa (Insecta Polyneoptera)
- Cawood, Rebecca, Nel, Andre, Garrouste, Romaine, Moyo, Sydney, Villet, Martin H, Prevec, Rosemary
- Authors: Cawood, Rebecca , Nel, Andre , Garrouste, Romaine , Moyo, Sydney , Villet, Martin H , Prevec, Rosemary
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/440723 , vital:73807 , https://hal.science/mnhn-04019993/
- Description: Here we describe a new genus and four new species of the extinct ‘Grylloblattida’: Liomopteridae Sellards, 1909: Liomopterum connexus Cawood and Nel, n. sp., Liomopterum daenerys Cawood and Nel, n. sp., Colubrosopterum karooensis Cawood and Nel, n. gen., n. sp., and Paraliomopterum sp. The fossil wings were collected from a new Middle Permian locality near Sutherland, Northern Cape, South Africa, with the horizon close to the Ecca-Beaufort Group contact in the southern Karoo Basin.
- Full Text:
- Date Issued: 2022
- Authors: Cawood, Rebecca , Nel, Andre , Garrouste, Romaine , Moyo, Sydney , Villet, Martin H , Prevec, Rosemary
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/440723 , vital:73807 , https://hal.science/mnhn-04019993/
- Description: Here we describe a new genus and four new species of the extinct ‘Grylloblattida’: Liomopteridae Sellards, 1909: Liomopterum connexus Cawood and Nel, n. sp., Liomopterum daenerys Cawood and Nel, n. sp., Colubrosopterum karooensis Cawood and Nel, n. gen., n. sp., and Paraliomopterum sp. The fossil wings were collected from a new Middle Permian locality near Sutherland, Northern Cape, South Africa, with the horizon close to the Ecca-Beaufort Group contact in the southern Karoo Basin.
- Full Text:
- Date Issued: 2022
The genetic architecture of the corpus callosum and its subregions
- Campbell, Megan M, Dalvie, Shareefa, Shadrin, Alexey, Van der Meer, Dennis, Andreassen, Ola, Stein, Dan J, Rokicki, Jaroslav
- Authors: Campbell, Megan M , Dalvie, Shareefa , Shadrin, Alexey , Van der Meer, Dennis , Andreassen, Ola , Stein, Dan J , Rokicki, Jaroslav
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/302542 , vital:58206 , xlink:href="https://doi.org/10.1016/j.euroneuro.2022.07.263"
- Description: Background: Regional surface area and thickness of the cerebral cortex and volume of subcortical structures are highly heritable brain morphological features with complex genetic architectures, involving many common genetic variants with small effect sizes. However, the genetic architecture of the corpus callosum (CC) and its subregions remains largely unclear. We aim to determine the heritability and genetic architecture of CC volume and each subregion and the extent to which this overlaps with that of psychiatric disorders. Methods: Genetic and T1-weighted MRI data of 40,894 individuals from the UK-biobank was used to construct a multivariate GWAS. Here, we utilized a multivariate approach (Multivariate Omnibus Statistical Test, MOSTest) to assess the distributive effects of common variants across the five subregions of the CC (posterior, mid posterior, central, mid anterior and anterior) obtained by running the automatic subcortical segmentation algorithm in FreeSurfer 5.3. Gene-set enrichment analyses were performed using MAGMA. Linkage disequilibrium score regression was used to determine the SNP-based heritability of the CC and will be used to assess the genetic correlation between each subregion and a variety of psychiatric disorders. Results: Following MOSTest, 70 independent loci show pooled effects across the 5 subregions of the CC (p more than 5×10-8). Using LDSC, we found evidence to suggest that CC volume is heritable (h2SNP= 0.38, SE=0.03). Significant variants showed enrichment in pathways related to regulation of the nervous system and cell development, neurogenesis, and regulation of neuron differentiation. Gene-set analysis revealed 156 significant genes (p is less than 2.6x10-6). Many of the significant SNPs have been previously associated with white matter hyperintensity volume as well as a range of psychiatric disorders. Discussion: Here we provide the first preliminary evidence to suggest that volume of the CC is heritable. Gene set enrichment analyses identified pathways related to neuron development and neurogenesis, suggesting that CC alteration may have an independent developmental origin. Further investigation into the shared genetic architecture of CC subregions and psychiatric disorders may provide novel insight into disease manifestation.
- Full Text:
- Date Issued: 2022
- Authors: Campbell, Megan M , Dalvie, Shareefa , Shadrin, Alexey , Van der Meer, Dennis , Andreassen, Ola , Stein, Dan J , Rokicki, Jaroslav
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/302542 , vital:58206 , xlink:href="https://doi.org/10.1016/j.euroneuro.2022.07.263"
- Description: Background: Regional surface area and thickness of the cerebral cortex and volume of subcortical structures are highly heritable brain morphological features with complex genetic architectures, involving many common genetic variants with small effect sizes. However, the genetic architecture of the corpus callosum (CC) and its subregions remains largely unclear. We aim to determine the heritability and genetic architecture of CC volume and each subregion and the extent to which this overlaps with that of psychiatric disorders. Methods: Genetic and T1-weighted MRI data of 40,894 individuals from the UK-biobank was used to construct a multivariate GWAS. Here, we utilized a multivariate approach (Multivariate Omnibus Statistical Test, MOSTest) to assess the distributive effects of common variants across the five subregions of the CC (posterior, mid posterior, central, mid anterior and anterior) obtained by running the automatic subcortical segmentation algorithm in FreeSurfer 5.3. Gene-set enrichment analyses were performed using MAGMA. Linkage disequilibrium score regression was used to determine the SNP-based heritability of the CC and will be used to assess the genetic correlation between each subregion and a variety of psychiatric disorders. Results: Following MOSTest, 70 independent loci show pooled effects across the 5 subregions of the CC (p more than 5×10-8). Using LDSC, we found evidence to suggest that CC volume is heritable (h2SNP= 0.38, SE=0.03). Significant variants showed enrichment in pathways related to regulation of the nervous system and cell development, neurogenesis, and regulation of neuron differentiation. Gene-set analysis revealed 156 significant genes (p is less than 2.6x10-6). Many of the significant SNPs have been previously associated with white matter hyperintensity volume as well as a range of psychiatric disorders. Discussion: Here we provide the first preliminary evidence to suggest that volume of the CC is heritable. Gene set enrichment analyses identified pathways related to neuron development and neurogenesis, suggesting that CC alteration may have an independent developmental origin. Further investigation into the shared genetic architecture of CC subregions and psychiatric disorders may provide novel insight into disease manifestation.
- Full Text:
- Date Issued: 2022