Chemical Profiling, Toxicity and Anti-Inflammatory Activities of Essential Oils from Three Grapefruit Cultivars from KwaZulu-Natal in South Africa
- Miya, Gugulethu, Oyedeji, Opeoluwa, Gondwe, Mavuto, Oyedeji, Adebola
- Authors: Miya, Gugulethu , Oyedeji, Opeoluwa , Gondwe, Mavuto , Oyedeji, Adebola
- Date: 2021-6
- Subjects: South Africa Citrus paradisi grapefruit essential oil toxicity anti-inflammatory Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6479 , vital:46408 , ("https://DOI:10.3390/molecules26113387")
- Description: Introduction: This case report discusses the successful use of an improvised bubble continuous positive airway pressure (CPAP) apparatus made using items commonly available in a poorly resourced district hospital. Case presentation: A 64-year-old female with no co-morbidities presented with respiratory failure due to pulmonary tuberculosis and was not accepted into the regional Intensive Care Unit (ICU) on referral. She required 8 days of improvised bubble CPAP to maintain adequate oxygen saturation before weaning and eventual discharge. Discussion: Improvised bubble CPAP is commonly used in neonatal care in developing countries and well described in literature however, there are no reports of its successful use in adult patients. In the absence of access to ICU or other Non-invasive ventilation (NIV) equipment, improvised bubble CPAP may provide some therapeutic benefit.
- Full Text:
- Date Issued: 2021-6
- Authors: Miya, Gugulethu , Oyedeji, Opeoluwa , Gondwe, Mavuto , Oyedeji, Adebola
- Date: 2021-6
- Subjects: South Africa Citrus paradisi grapefruit essential oil toxicity anti-inflammatory Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6479 , vital:46408 , ("https://DOI:10.3390/molecules26113387")
- Description: Introduction: This case report discusses the successful use of an improvised bubble continuous positive airway pressure (CPAP) apparatus made using items commonly available in a poorly resourced district hospital. Case presentation: A 64-year-old female with no co-morbidities presented with respiratory failure due to pulmonary tuberculosis and was not accepted into the regional Intensive Care Unit (ICU) on referral. She required 8 days of improvised bubble CPAP to maintain adequate oxygen saturation before weaning and eventual discharge. Discussion: Improvised bubble CPAP is commonly used in neonatal care in developing countries and well described in literature however, there are no reports of its successful use in adult patients. In the absence of access to ICU or other Non-invasive ventilation (NIV) equipment, improvised bubble CPAP may provide some therapeutic benefit.
- Full Text:
- Date Issued: 2021-6
Addressing the red flags in cochineal identification: The use of molecular techniques to identify cochineal insects that are used as biological control agents for invasive alien cacti
- van Steenderen, Clarke J M, Paterson, Iain D, Edwards, Shelley, Day, Michael D
- Authors: van Steenderen, Clarke J M , Paterson, Iain D , Edwards, Shelley , Day, Michael D
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/423282 , vital:72044 , xlink:href="https://doi.org/10.1016/j.biocontrol.2020.104426"
- Description: Invasive Cactaceae cause considerable damage to ecosystem function and agricultural practices around the world. The most successful biological control agents used to combat this group of weeds belong to the genus Dactylopius (Hemiptera: Dactylopiidae), commonly known as ‘cochineal’. Effective control relies on selecting the correct species, or in some cases, the most effective intraspecific lineage, of cochineal for the target cactus species. Many of the Dactylopius species are so morphologically similar, and in the case of intraspecific lineages, identical, that numerous misidentifications have been made in the past. These errors have resulted in failed attempts at the biological control of some cactus species. This study aimed to generate a multi-locus genetic database to enable the accurate identification of dactylopiids. Genetic characterization was achieved through the nucleotide sequencing of three gene regions (12S rRNA, 18S rRNA, and COI) and two inter-simple sequence repeats (ISSR). Nucleotide sequences were very effective for species-level and D. tomentosus lineage-level identification, but could not distinguish between the two lineages within D. opuntiae commonly used for biological control of various Opuntia spp. Fragment analysis through the use of ISSRs successfully addressed this issue. This is the first time that a method has been developed that can distinguish between these two D. opuntiae lineages. Using the methods developed in this study, biological control practitioners can ensure that the most effective agent species and lineages are used for each cactus target weed, thus maximizing the level of control.
- Full Text:
- Date Issued: 2021
- Authors: van Steenderen, Clarke J M , Paterson, Iain D , Edwards, Shelley , Day, Michael D
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/423282 , vital:72044 , xlink:href="https://doi.org/10.1016/j.biocontrol.2020.104426"
- Description: Invasive Cactaceae cause considerable damage to ecosystem function and agricultural practices around the world. The most successful biological control agents used to combat this group of weeds belong to the genus Dactylopius (Hemiptera: Dactylopiidae), commonly known as ‘cochineal’. Effective control relies on selecting the correct species, or in some cases, the most effective intraspecific lineage, of cochineal for the target cactus species. Many of the Dactylopius species are so morphologically similar, and in the case of intraspecific lineages, identical, that numerous misidentifications have been made in the past. These errors have resulted in failed attempts at the biological control of some cactus species. This study aimed to generate a multi-locus genetic database to enable the accurate identification of dactylopiids. Genetic characterization was achieved through the nucleotide sequencing of three gene regions (12S rRNA, 18S rRNA, and COI) and two inter-simple sequence repeats (ISSR). Nucleotide sequences were very effective for species-level and D. tomentosus lineage-level identification, but could not distinguish between the two lineages within D. opuntiae commonly used for biological control of various Opuntia spp. Fragment analysis through the use of ISSRs successfully addressed this issue. This is the first time that a method has been developed that can distinguish between these two D. opuntiae lineages. Using the methods developed in this study, biological control practitioners can ensure that the most effective agent species and lineages are used for each cactus target weed, thus maximizing the level of control.
- Full Text:
- Date Issued: 2021
Electrocatalytic activity of manganese tetra 4-aminophenyl porphyrin in the presence of graphene quantum dots
- Jokzai, Mbulelo, Mpeta, Lekhetho S, Nyokong, Tebello
- Authors: Jokzai, Mbulelo , Mpeta, Lekhetho S , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231443 , vital:49888 , xlink:href="https://doi.org/10.1016/j.molstruc.2015.02.040"
- Description: A manganese tetra 4-aminophenyl porphyrin (MnTAPP) was synthesized and attached to graphene quantum dots (GQDs) via covalent and π-π interaction to give MnTAPP@GQDs and MnTAPP--GQDs, respectively. There was an increase (using dynamic light scattering and transmission electron microscopy) in size of the GQDs in the presence of the porphyrin due to aggregation. The porphyrins in the absence and presence of GQDs were then adsorbed onto a glassy carbon electrode using drop and dry method. The electrochemical behavior was tested by cyclic voltammetry and chronoamperometry towards hydrazine. Both methods of combining MnTAPP with GQDs improved the activity of the electrocatalysis compared to individual components. MnTAPP@GQDs showed better catalytic rate constant of 4.36 × 102 Ms−1 and lowest LoD of 0.0023 mM followed by MnTAPP--GQDs. Furthermore, the sensor showed good selectivity in the presence of interfering analytes. All probes showed good stability.
- Full Text:
- Date Issued: 2021
- Authors: Jokzai, Mbulelo , Mpeta, Lekhetho S , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231443 , vital:49888 , xlink:href="https://doi.org/10.1016/j.molstruc.2015.02.040"
- Description: A manganese tetra 4-aminophenyl porphyrin (MnTAPP) was synthesized and attached to graphene quantum dots (GQDs) via covalent and π-π interaction to give MnTAPP@GQDs and MnTAPP--GQDs, respectively. There was an increase (using dynamic light scattering and transmission electron microscopy) in size of the GQDs in the presence of the porphyrin due to aggregation. The porphyrins in the absence and presence of GQDs were then adsorbed onto a glassy carbon electrode using drop and dry method. The electrochemical behavior was tested by cyclic voltammetry and chronoamperometry towards hydrazine. Both methods of combining MnTAPP with GQDs improved the activity of the electrocatalysis compared to individual components. MnTAPP@GQDs showed better catalytic rate constant of 4.36 × 102 Ms−1 and lowest LoD of 0.0023 mM followed by MnTAPP--GQDs. Furthermore, the sensor showed good selectivity in the presence of interfering analytes. All probes showed good stability.
- Full Text:
- Date Issued: 2021
Electrocatalytic activity of Schiff base containing copper phthalocyanines towards the detection of catechol
- Ndebele, Nobuhle, Sen, Pinar, Nyokong, Tebello
- Authors: Ndebele, Nobuhle , Sen, Pinar , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231410 , vital:49885 , xlink:href="https://doi.org/10.1016/j.poly.2021.115518"
- Description: In this study, four new copper phthalocyanine complexes were synthesised and studied as electrocatalysts for the detection of catechol. Two of these complexes were derived from a symmetrical benzaldehyde phthalocyanine complex via the condensation of the benzaldehyde substituents with amine reagents. The electrocatalysts proved to be highly stable towards the detection of catechol. The oxidation peaks obtained using cyclic voltammetry range from 0.20 to 0.38 V. Detection limits were obtained via chronoamperometry and are as low as 0.16 µM with fairly high sensitives being obtained. Overall all four copper complexes exhibited excellent electrocatalytic activity towards the electrooxidation of catechol.
- Full Text:
- Date Issued: 2021
- Authors: Ndebele, Nobuhle , Sen, Pinar , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231410 , vital:49885 , xlink:href="https://doi.org/10.1016/j.poly.2021.115518"
- Description: In this study, four new copper phthalocyanine complexes were synthesised and studied as electrocatalysts for the detection of catechol. Two of these complexes were derived from a symmetrical benzaldehyde phthalocyanine complex via the condensation of the benzaldehyde substituents with amine reagents. The electrocatalysts proved to be highly stable towards the detection of catechol. The oxidation peaks obtained using cyclic voltammetry range from 0.20 to 0.38 V. Detection limits were obtained via chronoamperometry and are as low as 0.16 µM with fairly high sensitives being obtained. Overall all four copper complexes exhibited excellent electrocatalytic activity towards the electrooxidation of catechol.
- Full Text:
- Date Issued: 2021
Enhanced upconversion emission of Er3+-Yb3+ co-doped Ba5 (PO4) 3OH powder phosphor for application in photodynamic therapy
- Mokoena, Puseletso P, Poluwole, David O, Nyokong, Tebello, Swart, Hendrik C, Ntwaeaborwa, Odireleng M
- Authors: Mokoena, Puseletso P , Poluwole, David O , Nyokong, Tebello , Swart, Hendrik C , Ntwaeaborwa, Odireleng M
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185035 , vital:44318 , xlink:href="https://doi.org/10.1016/j.sna.2021.113014"
- Description: Er3+-Yb3+ co-doped Ba5(PO4)3OH nanoparticle powder phosphors were successfully synthesized by urea combustion method. The resulting powder phosphors were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), high resolution scanning electron microscopy (HRSEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS) and photoluminescence spectroscopy (PL). XRD data confirmed crystallization of pure hexagonal phase of Ba5(PO4)3OH and HRSEM images showed formation of ellipsoidal particles. XPS data combined with EDS analysis confirmed the materials composition that corresponds with identification of all the chemical elements constituting the materials. The in vitro dark cytotoxicity of the particles confirmed lack of cytocidal behaviour in the absence of light, but considerable photodynamic therapy (PDT) activity was observed upon illumination. Upon excitation using a 980 nm laser, multiple emission peaks in the green and red regions corresponding to the optical transitions of Er3+ ion were observed. Upon co-doping with Yb3+, upconverted red emission was detected and this was attributable to non-radiative energy transfer from Yb3+ to Er3+. The proposed mechanism of upconversion photoluminescence is discussed.
- Full Text:
- Date Issued: 2021
- Authors: Mokoena, Puseletso P , Poluwole, David O , Nyokong, Tebello , Swart, Hendrik C , Ntwaeaborwa, Odireleng M
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185035 , vital:44318 , xlink:href="https://doi.org/10.1016/j.sna.2021.113014"
- Description: Er3+-Yb3+ co-doped Ba5(PO4)3OH nanoparticle powder phosphors were successfully synthesized by urea combustion method. The resulting powder phosphors were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), high resolution scanning electron microscopy (HRSEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS) and photoluminescence spectroscopy (PL). XRD data confirmed crystallization of pure hexagonal phase of Ba5(PO4)3OH and HRSEM images showed formation of ellipsoidal particles. XPS data combined with EDS analysis confirmed the materials composition that corresponds with identification of all the chemical elements constituting the materials. The in vitro dark cytotoxicity of the particles confirmed lack of cytocidal behaviour in the absence of light, but considerable photodynamic therapy (PDT) activity was observed upon illumination. Upon excitation using a 980 nm laser, multiple emission peaks in the green and red regions corresponding to the optical transitions of Er3+ ion were observed. Upon co-doping with Yb3+, upconverted red emission was detected and this was attributable to non-radiative energy transfer from Yb3+ to Er3+. The proposed mechanism of upconversion photoluminescence is discussed.
- Full Text:
- Date Issued: 2021
Human Papilloma Virus infection and cervical cancer among women who sell sex in Eastern and Southern Africa: A scoping review
- Macleod, Catriona I, Reynolds, John H
- Authors: Macleod, Catriona I , Reynolds, John H
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441228 , vital:73868 , xlink:href="https://doi.org/10.1177/17455065211058349"
- Description: Women who sell sex have a high prevalence of human papilloma virus, which may cause cervical cancer. The objective of this review was to collate findings on prevalence, associated factors, screening, service provision and utilization of services in relation to human papilloma virus and cervical cancer among women who sell sex in Eastern and Southern Africa.
- Full Text:
- Date Issued: 2021
- Authors: Macleod, Catriona I , Reynolds, John H
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441228 , vital:73868 , xlink:href="https://doi.org/10.1177/17455065211058349"
- Description: Women who sell sex have a high prevalence of human papilloma virus, which may cause cervical cancer. The objective of this review was to collate findings on prevalence, associated factors, screening, service provision and utilization of services in relation to human papilloma virus and cervical cancer among women who sell sex in Eastern and Southern Africa.
- Full Text:
- Date Issued: 2021
Modulation of the optical properties of chiral porphyrin dimers by introducing bridged chiral amide-bonds
- Qin, Mingfeng, Zhang, Zhen, Zhu, Weihua, Mack, John, Soy, Rodah C, Nyokong, Tebello, Liang, Xu
- Authors: Qin, Mingfeng , Zhang, Zhen , Zhu, Weihua , Mack, John , Soy, Rodah C , Nyokong, Tebello , Liang, Xu
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/190815 , vital:45031 , xlink:href="https://doi.org/10.1142/S1088424620500492"
- Description: The d/l-enantiomers of a series of three Zn(II)tetraarylporphyrin dimers were synthesized and isolated by incorporating a bridging amide-bonded xanthene moiety at the para-position of one of the meso-aryl rings. The electronic structures and optical properties were modulated by incorporating chiral amino acid moieties into the amide-bonding moieties of the xanthene bridge that contain methyl, tolyl and 2-methylindole substituents. A cofacial dimer was formed in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) resulting in a significant red shift of the B band, due to a relative destabilization of the HOMO, which has large MO coefficients on the pyrrole nitrogens. The sign sequences observed in the B band region of the CD spectra due to the presence of the chiral amino acid moieties were modified due to this change in geometry. Significant CD intensity is also observed in the B band region of the CD spectra of anion radical species during in situ spectroelectrochemical measurements.
- Full Text:
- Date Issued: 2021
- Authors: Qin, Mingfeng , Zhang, Zhen , Zhu, Weihua , Mack, John , Soy, Rodah C , Nyokong, Tebello , Liang, Xu
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/190815 , vital:45031 , xlink:href="https://doi.org/10.1142/S1088424620500492"
- Description: The d/l-enantiomers of a series of three Zn(II)tetraarylporphyrin dimers were synthesized and isolated by incorporating a bridging amide-bonded xanthene moiety at the para-position of one of the meso-aryl rings. The electronic structures and optical properties were modulated by incorporating chiral amino acid moieties into the amide-bonding moieties of the xanthene bridge that contain methyl, tolyl and 2-methylindole substituents. A cofacial dimer was formed in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) resulting in a significant red shift of the B band, due to a relative destabilization of the HOMO, which has large MO coefficients on the pyrrole nitrogens. The sign sequences observed in the B band region of the CD spectra due to the presence of the chiral amino acid moieties were modified due to this change in geometry. Significant CD intensity is also observed in the B band region of the CD spectra of anion radical species during in situ spectroelectrochemical measurements.
- Full Text:
- Date Issued: 2021
Perceptions of Cultural and Heritage Tourism Entrepreneurship among Students at a Higher Educational Institution in Cape Town
- Asoba, Samson Nambei, Patricia, Nteboheng Mefi
- Authors: Asoba, Samson Nambei , Patricia, Nteboheng Mefi
- Date: 2021
- Subjects: Heritage Tourism Entrepreneurship Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/8085 , vital:61394 , xlink:href="https://www.abacademies.org/articles/perceptions-of-cultural-and-heritage-tourism-entrepreneurship-among-students-at-a-higher-educational-institution-in-cape-town-13940.html"
- Description: This study was inspired by the need to increase entrepreneurial opportunities in South Africa. It analysed the opportunity presented by tourism as a possible entrepreneurial field for you entrepreneurs from Universities. The study was based on the position that despite the attacks on colonial heritage sites, they can present possible entrepreneurial opportunities. The study adopted the quantitative approach to collect and analyse the perceptions of entrepreneurship students at a Higher Education Institution. Evidence was found that there were many benefits of heritage entrepreneurship which included creating financial viability, creation of employment and improving the environment and infrastructure in communities. It was also found that most of the students held a positive impression of the role of tourist and tourism entrepreneurship in the communities. They held a good image of the tourist and felt that they did not offer any threat to locals. Youth are recommended to adopt heritage tourism entrepreneurship as employment opportunity.
- Full Text:
- Date Issued: 2021
- Authors: Asoba, Samson Nambei , Patricia, Nteboheng Mefi
- Date: 2021
- Subjects: Heritage Tourism Entrepreneurship Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/8085 , vital:61394 , xlink:href="https://www.abacademies.org/articles/perceptions-of-cultural-and-heritage-tourism-entrepreneurship-among-students-at-a-higher-educational-institution-in-cape-town-13940.html"
- Description: This study was inspired by the need to increase entrepreneurial opportunities in South Africa. It analysed the opportunity presented by tourism as a possible entrepreneurial field for you entrepreneurs from Universities. The study was based on the position that despite the attacks on colonial heritage sites, they can present possible entrepreneurial opportunities. The study adopted the quantitative approach to collect and analyse the perceptions of entrepreneurship students at a Higher Education Institution. Evidence was found that there were many benefits of heritage entrepreneurship which included creating financial viability, creation of employment and improving the environment and infrastructure in communities. It was also found that most of the students held a positive impression of the role of tourist and tourism entrepreneurship in the communities. They held a good image of the tourist and felt that they did not offer any threat to locals. Youth are recommended to adopt heritage tourism entrepreneurship as employment opportunity.
- Full Text:
- Date Issued: 2021
Photodynamic therapy activities of phthalocyanine-based macromolecular photosensitizers on MCF-7 breast cancer cells
- Ahmetali, Erem, Sen, Pinar, Süer, N Ceren, Nyokong, Tebello, Erin, Tarik, Sener, M Kasim
- Authors: Ahmetali, Erem , Sen, Pinar , Süer, N Ceren , Nyokong, Tebello , Erin, Tarik , Sener, M Kasim
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185655 , vital:44407 , xlink:href="https://doi.org/10.1080/10601325.2021.1934012"
- Description: Poly(oxanorbornene)s with zinc(II) phthalocyanine side chains have been synthesized by ring-opening metathesis polymerization. The incorporation of zinc(II) phthalocyanine into cationic polymer has given poly(oxanorbornene)s noteworthy photophysicochemical properties and the capacity to generate singlet oxygen under light irradiation. To investigate photosensitizer’s properties of the newly synthesized polymers P6 and P7: fluorescence (ΦF), singlet oxygen (ΦΔ) and triplet (ΦT) quantum yields of polymers have been measured in dimethyl sulfoxide and aqueous medium. Singlet oxygen quantum yields of P6 and P7 have been found to be 0.22 and 0.20 in dimethyl sulfoxide, respectively. Then, photodynamic therapy activities of polymers (P1-P7) against human breast adenocarcinoma cell line (MCF-7 cells) have been investigated. The copolymer P5 bearing pendant zinc(II) phthalocyanine and triethyl phosphonium functionalities has showed enhanced PDT activity with less than 10% viable cells at 60 μg/mL.
- Full Text:
- Date Issued: 2021
- Authors: Ahmetali, Erem , Sen, Pinar , Süer, N Ceren , Nyokong, Tebello , Erin, Tarik , Sener, M Kasim
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185655 , vital:44407 , xlink:href="https://doi.org/10.1080/10601325.2021.1934012"
- Description: Poly(oxanorbornene)s with zinc(II) phthalocyanine side chains have been synthesized by ring-opening metathesis polymerization. The incorporation of zinc(II) phthalocyanine into cationic polymer has given poly(oxanorbornene)s noteworthy photophysicochemical properties and the capacity to generate singlet oxygen under light irradiation. To investigate photosensitizer’s properties of the newly synthesized polymers P6 and P7: fluorescence (ΦF), singlet oxygen (ΦΔ) and triplet (ΦT) quantum yields of polymers have been measured in dimethyl sulfoxide and aqueous medium. Singlet oxygen quantum yields of P6 and P7 have been found to be 0.22 and 0.20 in dimethyl sulfoxide, respectively. Then, photodynamic therapy activities of polymers (P1-P7) against human breast adenocarcinoma cell line (MCF-7 cells) have been investigated. The copolymer P5 bearing pendant zinc(II) phthalocyanine and triethyl phosphonium functionalities has showed enhanced PDT activity with less than 10% viable cells at 60 μg/mL.
- Full Text:
- Date Issued: 2021
Photophysicochemical behaviour of phenoxy propanoic acid functionalised zinc phthalocyanines when grafted onto iron oxide and silica nanoparticles: Effects in photodynamic antimicrobial chemotherapy
- Dube, Edith, Soy, Rodah C, Shumba, Mumyaradzi, Nyokong, Tebello
- Authors: Dube, Edith , Soy, Rodah C , Shumba, Mumyaradzi , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185465 , vital:44389 , xlink:href="https://doi.org/10.1016/j.jlumin.2021.117939"
- Description: This work reports on the covalent linkage of (3-aminopropyl)triethoxysilane (APTES) functionalised iron oxide (IONPs–APTES) and silica (SiNPs–APTES) nanoparticles with zinc(II) tetra–([3–(4–phenoxy) propanoic acid) phthalocyanine] (1) and zinc(II) mono–([3–(4–phenoxy) propanoic acid) phthalocyanine (2) via an amide bond to form the conjugates, 1–IONPs-APTES, 1–SiNPs–APTES, 2-IONPs-APTES and 2-SiNPs-APTES). The photophysicochemical behaviour of the conjugates was investigated. These were characterized by a decrease in the fluorescence quantum yields and lifetimes, and an increase in the triplet quantum yield and singlet oxygen quantum yield when compared to complex 1 and 2 alone. The conjugates to IONPs-APTES displayed higher ΦT than those of SiNPs-APTES probably due to the heavy atom effect of iron compared to silica and the high loading capacity of the relatively smaller iron oxide NPs, however, there was no significant difference in the ΦΔ values of 2-IONPs-APTES (ΦΔ=0.59) and 2-SiNPs-APTES (ΦΔ=0.58), suggesting that the energy transfer process between the excited triplet state of 2-IONPs-APTES and ground state molecular oxygen was not effective. Photodynamic antimicrobial chemotherapy (PACT) studies showed that linkage of Pcs to NPs improves their photoinactivation capability against Staphylococcus aureus and Escherichia coli. IONPs-APTES and its conjugates generally displayed the highest log reductions than SiNPs-APTES and its conjugates except for studies after 75 min of irradiation for S. Aureus where the log reductions are the same. 2-IONP-APTES was recovered using a magnet after each photodegradation cycle and its stability after 3 cycles confirmed re-usability.
- Full Text:
- Date Issued: 2021
- Authors: Dube, Edith , Soy, Rodah C , Shumba, Mumyaradzi , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185465 , vital:44389 , xlink:href="https://doi.org/10.1016/j.jlumin.2021.117939"
- Description: This work reports on the covalent linkage of (3-aminopropyl)triethoxysilane (APTES) functionalised iron oxide (IONPs–APTES) and silica (SiNPs–APTES) nanoparticles with zinc(II) tetra–([3–(4–phenoxy) propanoic acid) phthalocyanine] (1) and zinc(II) mono–([3–(4–phenoxy) propanoic acid) phthalocyanine (2) via an amide bond to form the conjugates, 1–IONPs-APTES, 1–SiNPs–APTES, 2-IONPs-APTES and 2-SiNPs-APTES). The photophysicochemical behaviour of the conjugates was investigated. These were characterized by a decrease in the fluorescence quantum yields and lifetimes, and an increase in the triplet quantum yield and singlet oxygen quantum yield when compared to complex 1 and 2 alone. The conjugates to IONPs-APTES displayed higher ΦT than those of SiNPs-APTES probably due to the heavy atom effect of iron compared to silica and the high loading capacity of the relatively smaller iron oxide NPs, however, there was no significant difference in the ΦΔ values of 2-IONPs-APTES (ΦΔ=0.59) and 2-SiNPs-APTES (ΦΔ=0.58), suggesting that the energy transfer process between the excited triplet state of 2-IONPs-APTES and ground state molecular oxygen was not effective. Photodynamic antimicrobial chemotherapy (PACT) studies showed that linkage of Pcs to NPs improves their photoinactivation capability against Staphylococcus aureus and Escherichia coli. IONPs-APTES and its conjugates generally displayed the highest log reductions than SiNPs-APTES and its conjugates except for studies after 75 min of irradiation for S. Aureus where the log reductions are the same. 2-IONP-APTES was recovered using a magnet after each photodegradation cycle and its stability after 3 cycles confirmed re-usability.
- Full Text:
- Date Issued: 2021
Sex, gender and Uvalo/Letswalo centred spirituality
- Magadla, Siphokazi, Magoqwana, Babalwa, Motsemme, Nthabiseng, Mohoto, Lieketso
- Authors: Magadla, Siphokazi , Magoqwana, Babalwa , Motsemme, Nthabiseng , Mohoto, Lieketso
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/298663 , vital:57725 , xlink:href="https://doi.org/10.1080/02589001.2021.1909711"
- Description: In Male Daughters, Female Husbands (1987) Amadiume argues that the female orientation of Nnobi society and its emphasis on female industriousness is ‘derived from goddess Idemili – the ancestral religious deity’ (27). While Christianity dominates the outlook and conservatism of the post-colonial African state, we are seeing a growing public presence of African spiritual practitioners in southern Africa. The interview with Lieketso Gogo Mapitsi Mohoto reflects on her journey of becoming a healer. She uses the concept of ‘uvalo' to argue for deeper connected spiritual awareness within this practice of healing. Using the Nguni concept of uvalo, she refers to the fluid meaning of intuition also known as Umbilini among Xhosa-speaking people, while Sesotho speakers call it Letswalo. This intimate connection with the Divine can sometimes mean a sense of fear for ordinary people, while it promotes a deep sense of knowing for the spiritually conscious. Gogo Mapitsi's connections between spirituality and land, speak to Amadiume’s matrifocal understanding of productivity as linked to the goddess Idemili in Nnobi histories. Gogo Mapitsi reminds us that the multiple health, economic, psychological crises we face today are linked 'to how uvalo works.' She tells us that the 'cultivation of that inner knowing and the cultivation of trust in that knowing' is central to how a Sangoma understands and responds to the needs of their society.
- Full Text:
- Date Issued: 2021
- Authors: Magadla, Siphokazi , Magoqwana, Babalwa , Motsemme, Nthabiseng , Mohoto, Lieketso
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/298663 , vital:57725 , xlink:href="https://doi.org/10.1080/02589001.2021.1909711"
- Description: In Male Daughters, Female Husbands (1987) Amadiume argues that the female orientation of Nnobi society and its emphasis on female industriousness is ‘derived from goddess Idemili – the ancestral religious deity’ (27). While Christianity dominates the outlook and conservatism of the post-colonial African state, we are seeing a growing public presence of African spiritual practitioners in southern Africa. The interview with Lieketso Gogo Mapitsi Mohoto reflects on her journey of becoming a healer. She uses the concept of ‘uvalo' to argue for deeper connected spiritual awareness within this practice of healing. Using the Nguni concept of uvalo, she refers to the fluid meaning of intuition also known as Umbilini among Xhosa-speaking people, while Sesotho speakers call it Letswalo. This intimate connection with the Divine can sometimes mean a sense of fear for ordinary people, while it promotes a deep sense of knowing for the spiritually conscious. Gogo Mapitsi's connections between spirituality and land, speak to Amadiume’s matrifocal understanding of productivity as linked to the goddess Idemili in Nnobi histories. Gogo Mapitsi reminds us that the multiple health, economic, psychological crises we face today are linked 'to how uvalo works.' She tells us that the 'cultivation of that inner knowing and the cultivation of trust in that knowing' is central to how a Sangoma understands and responds to the needs of their society.
- Full Text:
- Date Issued: 2021
The complex relationship between asset wealth, adaptation, and diversification in tropical fisheries
- Taylor, Sarah F, Aswani, Shankar, Jiddawi, Narriman, Coupland, Jack, James, Phillip, Kelly, Stephen, Kizenga, Hellen, Roberts, Michael J, Popova, Ekaterina
- Authors: Taylor, Sarah F , Aswani, Shankar , Jiddawi, Narriman , Coupland, Jack , James, Phillip , Kelly, Stephen , Kizenga, Hellen , Roberts, Michael J , Popova, Ekaterina
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/403475 , vital:69964 , xlink:href="https://doi.org/10.1016/j.ocecoaman.2021.105808"
- Description: Marine small-scale fisheries are complex social and ecological systems that are currently pressurised by climate change, increasing demand for food, and expectation to sustain livelihoods. Species diversification and occupational diversification are often offered as adaptation strategies to increase the resilience of these fisheries to natural and economic shocks. However, little is known about the nature of species diversification within marine tropical fisheries. Based on 293 interviews with artisanal fishers from six coastal communities located at the isles of Zanzibar, Pemba, Mafia, and Mainland Tanga in Tanzania - we assess if fishers with the highest level of species diversification are the most financially secure and able to adapt to changes in the fishing industry. By creating an Asset Wealth Index (AWI) based on a Multiple Correspondence Approach (MCA), we investigate the relative levels of adaptive capacity and fishery connectivity within the different regional wealth quartiles. We find that less wealthy fishers target fewer species, making them less able to absorb changes in management measures focused on species, area, and closures. Likewise, fishers with higher wealth scores and higher adaptive capacity are able to better absorb the short-term losses of fisheries closures when compared to those with lower wealth and adaptive scores reliant on higher levels of fishery connectivity.
- Full Text:
- Date Issued: 2021
The complex relationship between asset wealth, adaptation, and diversification in tropical fisheries
- Authors: Taylor, Sarah F , Aswani, Shankar , Jiddawi, Narriman , Coupland, Jack , James, Phillip , Kelly, Stephen , Kizenga, Hellen , Roberts, Michael J , Popova, Ekaterina
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/403475 , vital:69964 , xlink:href="https://doi.org/10.1016/j.ocecoaman.2021.105808"
- Description: Marine small-scale fisheries are complex social and ecological systems that are currently pressurised by climate change, increasing demand for food, and expectation to sustain livelihoods. Species diversification and occupational diversification are often offered as adaptation strategies to increase the resilience of these fisheries to natural and economic shocks. However, little is known about the nature of species diversification within marine tropical fisheries. Based on 293 interviews with artisanal fishers from six coastal communities located at the isles of Zanzibar, Pemba, Mafia, and Mainland Tanga in Tanzania - we assess if fishers with the highest level of species diversification are the most financially secure and able to adapt to changes in the fishing industry. By creating an Asset Wealth Index (AWI) based on a Multiple Correspondence Approach (MCA), we investigate the relative levels of adaptive capacity and fishery connectivity within the different regional wealth quartiles. We find that less wealthy fishers target fewer species, making them less able to absorb changes in management measures focused on species, area, and closures. Likewise, fishers with higher wealth scores and higher adaptive capacity are able to better absorb the short-term losses of fisheries closures when compared to those with lower wealth and adaptive scores reliant on higher levels of fishery connectivity.
- Full Text:
- Date Issued: 2021
The photophysicochemical properties and photodynamic therapy activity of Schiff base substituted phthalocyanines doped into silica nanoparticles and conjugated to folic acid
- Magadla, Aviwe, Babu, Balaji, Sen, Pinar, Nyokong, Tebello
- Authors: Magadla, Aviwe , Babu, Balaji , Sen, Pinar , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185407 , vital:44384 , xlink:href="https://doi.org/10.1016/j.poly.2021.115227"
- Description: This work explores the synthesis, photophysicochemical properties and photodynamic activity (PDT) of tetrakis [N,N’–bis (4-(diethylamino)benzylidene) amino)propan-2-yl)oxy) phthalocyaninato] Zn (II) (3) and tetra-phenoxy N,N-dimethyl-4-((methylimino) Zn (II) (4) when the encapsulated into silica nanoparticles (SiNPs) followed by conjugation of folic acid (FA). The synthesised complexes and their doped analogues are examined for their PDT activity using MCF-7 cells. All the complexes showed dark toxicity that is >80%. The folic acid conjugates, MPc@SiNPs-FA showed greater photocytoxicity against MCF-7 cells upon irradiation with laser light.
- Full Text:
- Date Issued: 2021
- Authors: Magadla, Aviwe , Babu, Balaji , Sen, Pinar , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185407 , vital:44384 , xlink:href="https://doi.org/10.1016/j.poly.2021.115227"
- Description: This work explores the synthesis, photophysicochemical properties and photodynamic activity (PDT) of tetrakis [N,N’–bis (4-(diethylamino)benzylidene) amino)propan-2-yl)oxy) phthalocyaninato] Zn (II) (3) and tetra-phenoxy N,N-dimethyl-4-((methylimino) Zn (II) (4) when the encapsulated into silica nanoparticles (SiNPs) followed by conjugation of folic acid (FA). The synthesised complexes and their doped analogues are examined for their PDT activity using MCF-7 cells. All the complexes showed dark toxicity that is >80%. The folic acid conjugates, MPc@SiNPs-FA showed greater photocytoxicity against MCF-7 cells upon irradiation with laser light.
- Full Text:
- Date Issued: 2021
The Profit motive and the enabling environment for Growth of Survivalist Township Entrepreneurship: A Study at a Township in Cape Town
- Asoba, Samson Nambei, Patricia, Nteboheng Mefi
- Authors: Asoba, Samson Nambei , Patricia, Nteboheng Mefi
- Date: 2021
- Subjects: Small Business Entrepreneurship Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/8141 , vital:61398 , "https://www.abacademies.org/articles/the-profit-motive-and-the-enabling-environment-for-growth-of-survivalist-township-entrepreneurship-a-study-at-a-township-in-cape-t-10396.html"
- Description: The paper draws attention to the profit motive in respect of survivalist entrepreneurship at a township environment in Cape Town. Survivalist entrepreneurs have received little specific focus yet they represent a significant portion of economic activities in South Africa townships. Essentially the study considers the problem of failure to grow among survivalist entrepreneurs as reported in related literature. Many survivalist entrepreneurs fail to grow beyond the survivalist phase and there is no consensus on the underlying cause for such a phenomenon. With the Covid-19 pandemic, there is an expectation that survivalist entrepreneurs are likely to multiply owing to the collapse of many small businesses as well as the loss of employment arising from the pandemic. Two specific objective were formulated for the study: (1) to inquire into the business motives of survivalist entrepreneurs and (2) to assess the perception of the survivalist entrepreneurs on the degree to which the small business environment in supportive of motive attainment. The study adopted a quantitative research design based on the selection of respondents using a convenience sampling strategy. The evidence established from this study suggest that survivalist entrepreneurs do not pursue the profit motive significantly but they faced inhibitions presented by the economic environment in which they operate. Government and other stakeholders in the national economy are recommended to develop a suitable legal and institutional framework with strong structures to ensure the growth of survivalist entrepreneurs Keywords: Survivalist Entrepreneur, Township Entrepreneurship, Profit Motive, Small Businesses.
- Full Text:
- Date Issued: 2021
- Authors: Asoba, Samson Nambei , Patricia, Nteboheng Mefi
- Date: 2021
- Subjects: Small Business Entrepreneurship Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/8141 , vital:61398 , "https://www.abacademies.org/articles/the-profit-motive-and-the-enabling-environment-for-growth-of-survivalist-township-entrepreneurship-a-study-at-a-township-in-cape-t-10396.html"
- Description: The paper draws attention to the profit motive in respect of survivalist entrepreneurship at a township environment in Cape Town. Survivalist entrepreneurs have received little specific focus yet they represent a significant portion of economic activities in South Africa townships. Essentially the study considers the problem of failure to grow among survivalist entrepreneurs as reported in related literature. Many survivalist entrepreneurs fail to grow beyond the survivalist phase and there is no consensus on the underlying cause for such a phenomenon. With the Covid-19 pandemic, there is an expectation that survivalist entrepreneurs are likely to multiply owing to the collapse of many small businesses as well as the loss of employment arising from the pandemic. Two specific objective were formulated for the study: (1) to inquire into the business motives of survivalist entrepreneurs and (2) to assess the perception of the survivalist entrepreneurs on the degree to which the small business environment in supportive of motive attainment. The study adopted a quantitative research design based on the selection of respondents using a convenience sampling strategy. The evidence established from this study suggest that survivalist entrepreneurs do not pursue the profit motive significantly but they faced inhibitions presented by the economic environment in which they operate. Government and other stakeholders in the national economy are recommended to develop a suitable legal and institutional framework with strong structures to ensure the growth of survivalist entrepreneurs Keywords: Survivalist Entrepreneur, Township Entrepreneurship, Profit Motive, Small Businesses.
- Full Text:
- Date Issued: 2021
Turn-on detection of cysteine by a donor-acceptor type quinoline fluorophore: Exploring the sensing strategy and performance in bioimaging
- Muthusamy, Selvaraj, Zhao, Long, Rajalakshmi, Kanagaraj, Zhu, Dongwei, Soy, Rodah C, Mack, John, Nyokong, Tebello, Wang, Shengjun, Lee, Kang-Bong, Zhu, Weihua
- Authors: Muthusamy, Selvaraj , Zhao, Long , Rajalakshmi, Kanagaraj , Zhu, Dongwei , Soy, Rodah C , Mack, John , Nyokong, Tebello , Wang, Shengjun , Lee, Kang-Bong , Zhu, Weihua
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185644 , vital:44406 , xlink:href="https://doi.org/10.1016/j.dyepig.2021.109556"
- Description: Tracking the biothiol cysteine (Cys) in living systems is a significant responsibility to balance the redox environment and oxidative stress. A quinoline-7-nitro-1,2,3-benzoxadiazole (Q-NBD) fluorophore has been synthesized and characterized towards examination of Cys. The probe forms a quinoline-substituted phenol (Q-Ph-OH) after thiolysis of the NBD ether bond, leading to an increase of fluorescence at green channel. The turn-on sensing mechanism originates from the change in intramolecular charge transfer (ICT-OFF) along with an aggregation-induced emission (AIE) as suggested by spectroscopy measurements in solutions, time-dependent density-functional theory (TD-DFT) calculations and 1H NMR titration examination. Importantly, Q-NBD exhibited great sensitivity with a low limit of detection value of 89.5 nM and remarkable selectivity in various biothiols towards Cys. The sensor probe was successfully used for detecting both endogenous and exogenous Cys in PC3 living cells and spiked Cys in human urine samples.
- Full Text:
- Date Issued: 2021
- Authors: Muthusamy, Selvaraj , Zhao, Long , Rajalakshmi, Kanagaraj , Zhu, Dongwei , Soy, Rodah C , Mack, John , Nyokong, Tebello , Wang, Shengjun , Lee, Kang-Bong , Zhu, Weihua
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185644 , vital:44406 , xlink:href="https://doi.org/10.1016/j.dyepig.2021.109556"
- Description: Tracking the biothiol cysteine (Cys) in living systems is a significant responsibility to balance the redox environment and oxidative stress. A quinoline-7-nitro-1,2,3-benzoxadiazole (Q-NBD) fluorophore has been synthesized and characterized towards examination of Cys. The probe forms a quinoline-substituted phenol (Q-Ph-OH) after thiolysis of the NBD ether bond, leading to an increase of fluorescence at green channel. The turn-on sensing mechanism originates from the change in intramolecular charge transfer (ICT-OFF) along with an aggregation-induced emission (AIE) as suggested by spectroscopy measurements in solutions, time-dependent density-functional theory (TD-DFT) calculations and 1H NMR titration examination. Importantly, Q-NBD exhibited great sensitivity with a low limit of detection value of 89.5 nM and remarkable selectivity in various biothiols towards Cys. The sensor probe was successfully used for detecting both endogenous and exogenous Cys in PC3 living cells and spiked Cys in human urine samples.
- Full Text:
- Date Issued: 2021
Cross-sectional study of prevalence and determinants of uncontrolled hypertension among South African adult residents of Mkhondo municipality
- Masilela, Charity, Pearce, Brendon, Ongole, Joven Jebio, Adeniyi, Oladele Vincent, Benjeddou, Mongi
- Authors: Masilela, Charity , Pearce, Brendon , Ongole, Joven Jebio , Adeniyi, Oladele Vincent , Benjeddou, Mongi
- Date: 2020
- Subjects: Blood pressure control , Dyslipidaemia , Uncontrolled hypertension
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/11260/4481 , vital:44124 , https://doi.org/10.1186/s12889-020-09174-7
- Description: Achieving the blood pressure treatment target in individuals with hypertension is a serious global health challenge. Furthermore, the actual burden of uncontrolled hypertension is poorly understood, especially in the developing countries. Therefore, this study comprehensively examined the prevalence and factors associated with uncontrolled hypertension in individuals receiving care at the primary healthcare facilities in the rural areas of Mkhondo Municipality in the Mpumalanga Province, South Africa. Methods: In this cross-sectional study, 329 individuals attending care for hypertension were recruited from January 2019 to June 2019 at three primary healthcare centres, namely, Piet Retief hospital, Mkhondo town clinic and Thandukukhanya community health centre. Uncontrolled hypertension was defined as systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg in accordance with the South African Hypertension Society guideline (2014). Multiple logistic regression (Forward LR method) analysis was used to identify the significant determinants of uncontrolled hypertension. Results: The majority of the participants were 55 years old and above (69.0%), Zulus (81.2%), non-smokers (84.19%) and had been diagnosed with hypertension for more than a year prior to the study (72.64%). The overall prevalence of uncontrolled hypertension was 56.83% (n = 187) with no significant difference between sexes, 57.38% male versus 56.88% female, respectively. In the multiple logistic regression model analysis after adjusting for confounding variables, obesity (AOR = 2.90; 95% CI 1.66–5.05), physical activity (AOR = 4.79; 95% CI 2.15–10.65) and HDL-C (AOR = 5.66; 95% CI 3.33–9.60) were the significant and independent determinants of uncontrolled hypertension in the cohort. Conclusion: The high prevalence of uncontrolled hypertension in the study setting can be largely attributed to obesity, physical activity and dyslipidaemia. Treatment will require the collaborative efforts of individuals, clinicians and health authorities. All these determinants should be addressed decisively so as to achieve the treatment blood pressure targets in the study population.
- Full Text:
- Date Issued: 2020
- Authors: Masilela, Charity , Pearce, Brendon , Ongole, Joven Jebio , Adeniyi, Oladele Vincent , Benjeddou, Mongi
- Date: 2020
- Subjects: Blood pressure control , Dyslipidaemia , Uncontrolled hypertension
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/11260/4481 , vital:44124 , https://doi.org/10.1186/s12889-020-09174-7
- Description: Achieving the blood pressure treatment target in individuals with hypertension is a serious global health challenge. Furthermore, the actual burden of uncontrolled hypertension is poorly understood, especially in the developing countries. Therefore, this study comprehensively examined the prevalence and factors associated with uncontrolled hypertension in individuals receiving care at the primary healthcare facilities in the rural areas of Mkhondo Municipality in the Mpumalanga Province, South Africa. Methods: In this cross-sectional study, 329 individuals attending care for hypertension were recruited from January 2019 to June 2019 at three primary healthcare centres, namely, Piet Retief hospital, Mkhondo town clinic and Thandukukhanya community health centre. Uncontrolled hypertension was defined as systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg in accordance with the South African Hypertension Society guideline (2014). Multiple logistic regression (Forward LR method) analysis was used to identify the significant determinants of uncontrolled hypertension. Results: The majority of the participants were 55 years old and above (69.0%), Zulus (81.2%), non-smokers (84.19%) and had been diagnosed with hypertension for more than a year prior to the study (72.64%). The overall prevalence of uncontrolled hypertension was 56.83% (n = 187) with no significant difference between sexes, 57.38% male versus 56.88% female, respectively. In the multiple logistic regression model analysis after adjusting for confounding variables, obesity (AOR = 2.90; 95% CI 1.66–5.05), physical activity (AOR = 4.79; 95% CI 2.15–10.65) and HDL-C (AOR = 5.66; 95% CI 3.33–9.60) were the significant and independent determinants of uncontrolled hypertension in the cohort. Conclusion: The high prevalence of uncontrolled hypertension in the study setting can be largely attributed to obesity, physical activity and dyslipidaemia. Treatment will require the collaborative efforts of individuals, clinicians and health authorities. All these determinants should be addressed decisively so as to achieve the treatment blood pressure targets in the study population.
- Full Text:
- Date Issued: 2020
Detecting change in local ecological knowledge: An application of an index of taxonomic distinctness to an ethnoichthyological classification in the Solomon Islands
- Aswani, Shankar, Ferse, Sebastien C A, Stäbler, Moritz, Chong-Montenegro, Carolina
- Authors: Aswani, Shankar , Ferse, Sebastien C A , Stäbler, Moritz , Chong-Montenegro, Carolina
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/406521 , vital:70282 , xlink:href="https://doi.org/10.1016/j.ecolind.2020.106865"
- Description: The global accelerating loss of biodiversity is having immediate repercussions for ecosystems and human wellbeing, particularly in areas where people depend intimately on their natural environment for their livelihoods. Dovetailing this loss is the demise of local/traditional knowledge systems resulting from factors such as changing lifestyle and the transformation of local belief systems. While the importance of local ecological knowledge (LEK) for documentation of biodiversity and environmental change and development of management responses is well established, quantitative tools to analyze and systematically compare LEK are scarce. In this research, we analyze the complexity of local ecological knowledge used by respondents to classify locally-recognized marine species. We do so by applying a modified index of taxonomic distinctness to an ethnoichthyological classification in coastal communities in the Solomon Islands. In addition, we assess simple taxonomic diversity (richness in locally-recognized species names) by comparing taxonomies collected in 1992–1995 and 2014–2015. Results indicate that both endogenous (gender, age) and exogenous (proximity to market) factors have discernible effects on folk taxonomic knowledge in the region, with younger respondents and communities closer to a regional market center displaying a significantly lower richness of local species names. Folk taxonomic distinctness was significantly reduced closer to the regional market. The modified index of taxonomic distinctness applied in this research provides a useful tool to explore facets of local ecological knowledge in addition to simple richness of terms, and to compare across different regions and cultural backgrounds. Understanding changes in LEK is important because such knowledge enables communities who are highly dependent on living natural resources to harvest and manage resources more efficiently and also to detect and react to environmental change.
- Full Text:
- Date Issued: 2020
- Authors: Aswani, Shankar , Ferse, Sebastien C A , Stäbler, Moritz , Chong-Montenegro, Carolina
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/406521 , vital:70282 , xlink:href="https://doi.org/10.1016/j.ecolind.2020.106865"
- Description: The global accelerating loss of biodiversity is having immediate repercussions for ecosystems and human wellbeing, particularly in areas where people depend intimately on their natural environment for their livelihoods. Dovetailing this loss is the demise of local/traditional knowledge systems resulting from factors such as changing lifestyle and the transformation of local belief systems. While the importance of local ecological knowledge (LEK) for documentation of biodiversity and environmental change and development of management responses is well established, quantitative tools to analyze and systematically compare LEK are scarce. In this research, we analyze the complexity of local ecological knowledge used by respondents to classify locally-recognized marine species. We do so by applying a modified index of taxonomic distinctness to an ethnoichthyological classification in coastal communities in the Solomon Islands. In addition, we assess simple taxonomic diversity (richness in locally-recognized species names) by comparing taxonomies collected in 1992–1995 and 2014–2015. Results indicate that both endogenous (gender, age) and exogenous (proximity to market) factors have discernible effects on folk taxonomic knowledge in the region, with younger respondents and communities closer to a regional market center displaying a significantly lower richness of local species names. Folk taxonomic distinctness was significantly reduced closer to the regional market. The modified index of taxonomic distinctness applied in this research provides a useful tool to explore facets of local ecological knowledge in addition to simple richness of terms, and to compare across different regions and cultural backgrounds. Understanding changes in LEK is important because such knowledge enables communities who are highly dependent on living natural resources to harvest and manage resources more efficiently and also to detect and react to environmental change.
- Full Text:
- Date Issued: 2020
Ethics and education as practices of freedom
- Authors: Tabensky, Pedro
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/305672 , vital:58602 , xlink:href="https://doi.org/10.1080/00131857.2020.1791822"
- Description: On the one hand, according to Richard Rorty, Paulo Freire and others, education is the practice of freedom. On the other hand, according to Michael Foucault, Mary Midgley and others, ethics is the practice of freedom. How, then, are education and ethics related to one another and what do these authors mean by ‘the practice of freedom’? In this piece, I argue that education and ethics are two mutually constitutive aspects of the practice of freedom. Individuals who are able to engage in this practice can most properly be said to be the authors of their lives, that is, individuals who, to borrow from Neil MacGregor, are able to find their ‘place in things’. To find our ‘place in things’ is to do the necessary educative work required for becoming the authors of our lives, that is, for self-actualization (as Rorty and John Dewey have argued). To take on the authorial role is, moreover, to be able effectively to take control of our lives, to organize them into unities for which we are individually responsible. This, according to Midgley, is precisely what it is to be ethical. This work, moreover, requires ongoing development, that is, education, in Dewey’s sense. I further argue that professional education and skills training cannot be understood properly in isolation from these broader educational aims and I criticize mainstream educational practices for not paying sufficient attention to the intimate relationship between the vocational and non-vocational aspects of education.
- Full Text:
- Date Issued: 2020
- Authors: Tabensky, Pedro
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/305672 , vital:58602 , xlink:href="https://doi.org/10.1080/00131857.2020.1791822"
- Description: On the one hand, according to Richard Rorty, Paulo Freire and others, education is the practice of freedom. On the other hand, according to Michael Foucault, Mary Midgley and others, ethics is the practice of freedom. How, then, are education and ethics related to one another and what do these authors mean by ‘the practice of freedom’? In this piece, I argue that education and ethics are two mutually constitutive aspects of the practice of freedom. Individuals who are able to engage in this practice can most properly be said to be the authors of their lives, that is, individuals who, to borrow from Neil MacGregor, are able to find their ‘place in things’. To find our ‘place in things’ is to do the necessary educative work required for becoming the authors of our lives, that is, for self-actualization (as Rorty and John Dewey have argued). To take on the authorial role is, moreover, to be able effectively to take control of our lives, to organize them into unities for which we are individually responsible. This, according to Midgley, is precisely what it is to be ethical. This work, moreover, requires ongoing development, that is, education, in Dewey’s sense. I further argue that professional education and skills training cannot be understood properly in isolation from these broader educational aims and I criticize mainstream educational practices for not paying sufficient attention to the intimate relationship between the vocational and non-vocational aspects of education.
- Full Text:
- Date Issued: 2020
In Vitro Studies on Antioxidant and AntiParasitic Activities of Compounds Isolated from Rauvolfia caffra Sond
- Tlhapi, Dorcas B, Ramaite, Isaiah D, Anokwuru, Chinedu P, van Ree, Teunis, Hoppe, Heinrich C
- Authors: Tlhapi, Dorcas B , Ramaite, Isaiah D , Anokwuru, Chinedu P , van Ree, Teunis , Hoppe, Heinrich C
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/425993 , vital:72305 , xlink:href="https://doi.org/10.3390/molecules25173781"
- Description: As part of an ongoing study of natural products from local medicinal plants, the methanol extract of stem bark of Rauvolfia caffra Sond was investigated for biological activity. Column chromatography and preparative thin-layer chromatography were used to isolate lupeol (1), raucaffricine (2), N-methylsarpagine (3), and spegatrine (4). The crude extract, fractions and isolated compounds were tested for anti-oxidant, antitrypanosomal and anti-proliferation activities. Two fractions displayed high DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging activity and reducing power with IC50 (The half maximal inhibitory concentration) and IC0.5 values of 0.022 ± 0.003 mg/mL and 0.036 ± 0.007 mg/mL, and 0.518 ± 0.044 mg/mL and 1.076 ± 0.136 mg/mL, respectively. Spegatrine (4) was identified as the main antioxidant compound in R. caffra with IC50 and IC0.5 values of 0.119 ± 0.067 mg/mL and 0.712 ± 0 mg/mL, respectively. One fraction displayed high antitrypanosomal activity with an IC50 value of 18.50 μg/mL. However, the major constituent of this fraction, raucaffricine (2), was not active. The crude extract, fractions and pure compounds did not display any cytotoxic effect at a concentration of 50 μg/mL against HeLa cells. This study shows directions for further in vitro studies on the antioxidant and antitrypanosomal activities of Rauvolfia caffra Sond.
- Full Text:
- Date Issued: 2020
- Authors: Tlhapi, Dorcas B , Ramaite, Isaiah D , Anokwuru, Chinedu P , van Ree, Teunis , Hoppe, Heinrich C
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/425993 , vital:72305 , xlink:href="https://doi.org/10.3390/molecules25173781"
- Description: As part of an ongoing study of natural products from local medicinal plants, the methanol extract of stem bark of Rauvolfia caffra Sond was investigated for biological activity. Column chromatography and preparative thin-layer chromatography were used to isolate lupeol (1), raucaffricine (2), N-methylsarpagine (3), and spegatrine (4). The crude extract, fractions and isolated compounds were tested for anti-oxidant, antitrypanosomal and anti-proliferation activities. Two fractions displayed high DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging activity and reducing power with IC50 (The half maximal inhibitory concentration) and IC0.5 values of 0.022 ± 0.003 mg/mL and 0.036 ± 0.007 mg/mL, and 0.518 ± 0.044 mg/mL and 1.076 ± 0.136 mg/mL, respectively. Spegatrine (4) was identified as the main antioxidant compound in R. caffra with IC50 and IC0.5 values of 0.119 ± 0.067 mg/mL and 0.712 ± 0 mg/mL, respectively. One fraction displayed high antitrypanosomal activity with an IC50 value of 18.50 μg/mL. However, the major constituent of this fraction, raucaffricine (2), was not active. The crude extract, fractions and pure compounds did not display any cytotoxic effect at a concentration of 50 μg/mL against HeLa cells. This study shows directions for further in vitro studies on the antioxidant and antitrypanosomal activities of Rauvolfia caffra Sond.
- Full Text:
- Date Issued: 2020
Investigation of electrocatalytic behaviour of low symmetry cobalt phthalocyanines when clicked to azide grafted carbon electrodes
- Mpeta, Lakethe S, Sen, Pinar, Nyokong, Tebello
- Authors: Mpeta, Lakethe S , Sen, Pinar , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186304 , vital:44483 , xlink:href="https://doi.org/10.1016/j.jelechem.2020.113896"
- Description: This work describes the electrochemical properties of low symmetry cobalt phthalocyanines namely, tris-[(4-tert-butylphenoxy)-4-(pent-4-yn-1-yloxy) phthalocyaniato] cobalt (II) (3) and tris-[(4-tert-butylphenoxy)-4-(4-ethybylbenzyl-oxy) phthalocyaniato] cobalt (II) (5). The complexes were characterized by a number of techniques including UV–Vis, mass, and infrared spectra, as well as elemental analysis. The glassy carbon electrodes were first azide functionalized then clicked to low symmetry phthalocyanines. The click reaction was confirmed using X-ray photoelectron spectra. The constructed electrodes showed excellent electrocatalytic activity towards hydrazine oxidation. Oxidation peaks with low potentials of 0.21 V and 0.26 V, for complexes 3 and 5, respectively were obtained. Complex-5 gave a better detection limit of 0.94 μM and electrocatalytic rate constant of 5.6 × 106 M−1 s−1.
- Full Text:
- Date Issued: 2020
- Authors: Mpeta, Lakethe S , Sen, Pinar , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186304 , vital:44483 , xlink:href="https://doi.org/10.1016/j.jelechem.2020.113896"
- Description: This work describes the electrochemical properties of low symmetry cobalt phthalocyanines namely, tris-[(4-tert-butylphenoxy)-4-(pent-4-yn-1-yloxy) phthalocyaniato] cobalt (II) (3) and tris-[(4-tert-butylphenoxy)-4-(4-ethybylbenzyl-oxy) phthalocyaniato] cobalt (II) (5). The complexes were characterized by a number of techniques including UV–Vis, mass, and infrared spectra, as well as elemental analysis. The glassy carbon electrodes were first azide functionalized then clicked to low symmetry phthalocyanines. The click reaction was confirmed using X-ray photoelectron spectra. The constructed electrodes showed excellent electrocatalytic activity towards hydrazine oxidation. Oxidation peaks with low potentials of 0.21 V and 0.26 V, for complexes 3 and 5, respectively were obtained. Complex-5 gave a better detection limit of 0.94 μM and electrocatalytic rate constant of 5.6 × 106 M−1 s−1.
- Full Text:
- Date Issued: 2020