Electrografting of isophthalic acid monolayer and covalent attachment of antibody onto carbon surfaces
- Mwanza, Daniel, Phal, Sereilakhena, Nyokong, Tebello, Tesfalidet, Solomon, Mashazi, Philani N
- Authors: Mwanza, Daniel , Phal, Sereilakhena , Nyokong, Tebello , Tesfalidet, Solomon , Mashazi, Philani N
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231345 , vital:49879 , xlink:href="https://doi.org/10.1016/j.electacta.2021.139360"
- Description: In this study, a 5-diazonium isophthalic acid was synthesized and electrografted onto glassy carbon (GCE) and screen-printed carbon (SPCE) electrodes. SPCE was used to demonstrate fabrication of a miniature device and to compare with conventional glassy carbon electrodes. The isophthalic acid (IPA) electrografted thin film was used for the immobilization of anti-methotrexate antibody (Ab) using carbodiimide activation chemistry to form antibody modified surfaces, GCE-IPA-Ab and SPCE-IPA-Ab. The GCE -IPA-Ab and SPCE-IPA-Ab surfaces were used as capacitive biosensors for the detection of methotrexate (MTX) in phosphate buffer (pH 7.4) using capacitive electrochemical impedance spectroscopy (EIS). The EIS data was analyzed using singular value decomposition (SVD). Principal component regression analysis gave R2 values of 0.99 for both the GCE-IPA-Ab and SPCE-IPA-Ab surfaces. The detection limit from the calibration curve of the GCE-IPA-Ab and SPCE-IPA-Ab was calculated to be 7.0 pmol.L−1 and 5.5 pmol.L−1, respectively.
- Full Text:
- Date Issued: 2021
- Authors: Mwanza, Daniel , Phal, Sereilakhena , Nyokong, Tebello , Tesfalidet, Solomon , Mashazi, Philani N
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231345 , vital:49879 , xlink:href="https://doi.org/10.1016/j.electacta.2021.139360"
- Description: In this study, a 5-diazonium isophthalic acid was synthesized and electrografted onto glassy carbon (GCE) and screen-printed carbon (SPCE) electrodes. SPCE was used to demonstrate fabrication of a miniature device and to compare with conventional glassy carbon electrodes. The isophthalic acid (IPA) electrografted thin film was used for the immobilization of anti-methotrexate antibody (Ab) using carbodiimide activation chemistry to form antibody modified surfaces, GCE-IPA-Ab and SPCE-IPA-Ab. The GCE -IPA-Ab and SPCE-IPA-Ab surfaces were used as capacitive biosensors for the detection of methotrexate (MTX) in phosphate buffer (pH 7.4) using capacitive electrochemical impedance spectroscopy (EIS). The EIS data was analyzed using singular value decomposition (SVD). Principal component regression analysis gave R2 values of 0.99 for both the GCE-IPA-Ab and SPCE-IPA-Ab surfaces. The detection limit from the calibration curve of the GCE-IPA-Ab and SPCE-IPA-Ab was calculated to be 7.0 pmol.L−1 and 5.5 pmol.L−1, respectively.
- Full Text:
- Date Issued: 2021
Enhanced photo-ablation effect of positively charged phthalocyanines-detonation nanodiamonds nanoplatforms for the suppression of Staphylococcus aureus and Escherichia coli planktonic cells and biofilms
- Openda, Yolande I, Nyokong, Tebello
- Authors: Openda, Yolande I , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185712 , vital:44417 , xlink:href="https://doi.org/10.1016/j.jphotochem.2021.113200"
- Description: Photodynamic antimicrobial therapy (PACT) is a powerful technic recommended to eliminate life-threatening pathogens that cause localized and superficial infections as pathogens cannot develop resistance to it. For this reason, new positively charged chalcone substituted zinc (3a) and indium (4a) metalated phthalocyanines (Pcs) were synthesized and were π-π interacted with detonation nanodiamonds (DNDs) nanoparticles to form new water soluble nanoplatfoms 3a@DNDs and 4a@DNDs. The conjugates generated high singlet oxygen quantum yields (ΦΔ) in water (1% DMSO, used for PACT studies) with values of 0.46 and 0.47 for 3a@DNDs and 4a@DNDs, respectively. Hence, they were tested for PACT against biofilms of S. aureus and E. coli, as well as their planktonic cells. The quaternized Pcs alone 3a and 4a as well as their nanoconjugates 3a@DNDs and 4a@DNDs were effective PACT agents with log10 CFU > 9 for E. coli and S. aureus. The quaternized derivatives were found to have higher ability to completely suppress both planktonic and biofilms of S. aureus and E. coli in vitro. Therefore, they could be used as appropriate photosensitive agents.
- Full Text:
- Date Issued: 2021
- Authors: Openda, Yolande I , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185712 , vital:44417 , xlink:href="https://doi.org/10.1016/j.jphotochem.2021.113200"
- Description: Photodynamic antimicrobial therapy (PACT) is a powerful technic recommended to eliminate life-threatening pathogens that cause localized and superficial infections as pathogens cannot develop resistance to it. For this reason, new positively charged chalcone substituted zinc (3a) and indium (4a) metalated phthalocyanines (Pcs) were synthesized and were π-π interacted with detonation nanodiamonds (DNDs) nanoparticles to form new water soluble nanoplatfoms 3a@DNDs and 4a@DNDs. The conjugates generated high singlet oxygen quantum yields (ΦΔ) in water (1% DMSO, used for PACT studies) with values of 0.46 and 0.47 for 3a@DNDs and 4a@DNDs, respectively. Hence, they were tested for PACT against biofilms of S. aureus and E. coli, as well as their planktonic cells. The quaternized Pcs alone 3a and 4a as well as their nanoconjugates 3a@DNDs and 4a@DNDs were effective PACT agents with log10 CFU > 9 for E. coli and S. aureus. The quaternized derivatives were found to have higher ability to completely suppress both planktonic and biofilms of S. aureus and E. coli in vitro. Therefore, they could be used as appropriate photosensitive agents.
- 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
Enhancement of Biological and Pharmacological Properties of an Encapsulated Polyphenol: Curcumin
- Witika, Bwalya A, Makoni, Pedzisai A, Matafwali, Scott K, Mweetwa, Larry L, Shandele, Ginnethon C, Walker, Roderick B
- Authors: Witika, Bwalya A , Makoni, Pedzisai A , Matafwali, Scott K , Mweetwa, Larry L , Shandele, Ginnethon C , Walker, Roderick B
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183161 , vital:43917 , xlink:href="https://doi.org/10.3390/molecules26144244"
- Description: There is a dearth of natural remedies available for the treatment of an increasing number of diseases facing mankind. Natural products may provide an opportunity to produce formulations and therapeutic solutions to address this shortage. Curcumin (CUR), diferuloylmethane; I,7-bis-(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione is the major pigment in turmeric powder which has been reported to exhibit a number of health benefits including, antibacterial, antiviral, anti-cancer, anti-inflammatory and anti-oxidant properties. In this review, the authors attempt to highlight the biological and pharmacological properties of CUR in addition to emphasizing aspects relating to the biosynthesis, encapsulation and therapeutic effects of the compound. The information contained in this review was generated by considering published information in which evidence of enhanced biological and pharmacological properties of nano-encapsulated CUR was reported. CUR has contributed to a significant improvement in melanoma, breast, lung, gastro-intestinal, and genito-urinary cancer therapy. We highlight the impact of nano-encapsulated CUR for efficient inhibition of cell proliferation, even at low concentrations compared to the free CUR when considering anti-proliferation. Furthermore nano-encapsulated CUR exhibited bioactive properties, exerted cytotoxic and anti-oxidant effects by acting on endogenous and cholinergic anti-oxidant systems. CUR was reported to block Hepatitis C virus (HCV) entry into hepatic cells, inhibit MRSA proliferation, enhance wound healing and reduce bacterial load. Nano-encapsulated CUR has also shown bioactive properties when acting on antioxidant systems (endogenous and cholinergic). Future research is necessary and must focus on investigation of encapsulated CUR nano-particles in different models of human pathology.
- Full Text:
- Date Issued: 2021
- Authors: Witika, Bwalya A , Makoni, Pedzisai A , Matafwali, Scott K , Mweetwa, Larry L , Shandele, Ginnethon C , Walker, Roderick B
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183161 , vital:43917 , xlink:href="https://doi.org/10.3390/molecules26144244"
- Description: There is a dearth of natural remedies available for the treatment of an increasing number of diseases facing mankind. Natural products may provide an opportunity to produce formulations and therapeutic solutions to address this shortage. Curcumin (CUR), diferuloylmethane; I,7-bis-(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione is the major pigment in turmeric powder which has been reported to exhibit a number of health benefits including, antibacterial, antiviral, anti-cancer, anti-inflammatory and anti-oxidant properties. In this review, the authors attempt to highlight the biological and pharmacological properties of CUR in addition to emphasizing aspects relating to the biosynthesis, encapsulation and therapeutic effects of the compound. The information contained in this review was generated by considering published information in which evidence of enhanced biological and pharmacological properties of nano-encapsulated CUR was reported. CUR has contributed to a significant improvement in melanoma, breast, lung, gastro-intestinal, and genito-urinary cancer therapy. We highlight the impact of nano-encapsulated CUR for efficient inhibition of cell proliferation, even at low concentrations compared to the free CUR when considering anti-proliferation. Furthermore nano-encapsulated CUR exhibited bioactive properties, exerted cytotoxic and anti-oxidant effects by acting on endogenous and cholinergic anti-oxidant systems. CUR was reported to block Hepatitis C virus (HCV) entry into hepatic cells, inhibit MRSA proliferation, enhance wound healing and reduce bacterial load. Nano-encapsulated CUR has also shown bioactive properties when acting on antioxidant systems (endogenous and cholinergic). Future research is necessary and must focus on investigation of encapsulated CUR nano-particles in different models of human pathology.
- Full Text:
- Date Issued: 2021
Environmental entrepreneurship as an innovation catalyst for social change: A systematic review as a basis for future research
- Diale, Dineo, Kanakana-Katumba, Mukondeleli G, Maladzhi, Rendani W
- Authors: Diale, Dineo , Kanakana-Katumba, Mukondeleli G , Maladzhi, Rendani W
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/450641 , vital:74970 , xlink:href="https://www.astesj.com/publications/ASTESJ_060145.pdf"
- Description: There are pressures to adopt sustainable behaviour more so in generating profits and benefiting the society to accelerate green efforts through a green framework. The overarching goal of the paper is premised through various works of literature, building the ecosystem the elements highlighted by most researchers in the field of environmental entrepreneurship. The various models reviewed consists of generic incubators and entrepreneurship, and societal and environmental factors. Environmental entrepreneurship is often used interchangeably with concepts such as green entrepreneurship and ecopreneurship which under-researched globally, with non-existent efforts on the applicability and modelling of key environmental entrepreneurship within a specific context utilising the system dynamics approach. In order to assess the environmental entrepreneurship ecosystem, the authors adopted a system dynamic approach to determine key variables that enable the development of the system. A literature review was conducted, and of the 135 articles reviewed, n= 92 peer-reviewed articles met the criteria that the researchers set. Some of the results emanating from a systematic review are environmental policy, green skills, financial and non-financial support, societal and behavioural factors, environmental agility, ethics and governance, and access to markets. The theoretical results are simulated using system dynamics modelling. Due to limited research on the abovementioned topic, a possible impacting variable (Exogenous variables) was broadened to add value to, and have an impact on, the study. Upon reviewing the above-mentioned models, the framework emerged signalling elements to be simulated in the system dynamics model, which were then theoretically contextualised for the South African context. The theoretical virtual system dynamic model forming part of the framework will be tested and validated in the next study. The applicability of the theoretical ecosystem to South African context as well as future recommendations are provided in the study.
- Full Text:
- Date Issued: 2021
- Authors: Diale, Dineo , Kanakana-Katumba, Mukondeleli G , Maladzhi, Rendani W
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/450641 , vital:74970 , xlink:href="https://www.astesj.com/publications/ASTESJ_060145.pdf"
- Description: There are pressures to adopt sustainable behaviour more so in generating profits and benefiting the society to accelerate green efforts through a green framework. The overarching goal of the paper is premised through various works of literature, building the ecosystem the elements highlighted by most researchers in the field of environmental entrepreneurship. The various models reviewed consists of generic incubators and entrepreneurship, and societal and environmental factors. Environmental entrepreneurship is often used interchangeably with concepts such as green entrepreneurship and ecopreneurship which under-researched globally, with non-existent efforts on the applicability and modelling of key environmental entrepreneurship within a specific context utilising the system dynamics approach. In order to assess the environmental entrepreneurship ecosystem, the authors adopted a system dynamic approach to determine key variables that enable the development of the system. A literature review was conducted, and of the 135 articles reviewed, n= 92 peer-reviewed articles met the criteria that the researchers set. Some of the results emanating from a systematic review are environmental policy, green skills, financial and non-financial support, societal and behavioural factors, environmental agility, ethics and governance, and access to markets. The theoretical results are simulated using system dynamics modelling. Due to limited research on the abovementioned topic, a possible impacting variable (Exogenous variables) was broadened to add value to, and have an impact on, the study. Upon reviewing the above-mentioned models, the framework emerged signalling elements to be simulated in the system dynamics model, which were then theoretically contextualised for the South African context. The theoretical virtual system dynamic model forming part of the framework will be tested and validated in the next study. The applicability of the theoretical ecosystem to South African context as well as future recommendations are provided in the study.
- Full Text:
- Date Issued: 2021
Ethnobotanical survey, phytoconstituents and antibacterial investigation of Rapanea melanophloeos (L.) Mez. bark, fruit and leaf extracts
- Lukhele, Thabile, Olivier, Denise, Tata, Charlotte, Ikhile, Monisola I, Krause, Rui W M, van Vuuren, Sandy, Ndineh, Derek T
- Authors: Lukhele, Thabile , Olivier, Denise , Tata, Charlotte , Ikhile, Monisola I , Krause, Rui W M , van Vuuren, Sandy , Ndineh, Derek T
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/191791 , vital:45164 , xlink:href="https://doi.org/10.1515/psr-2020-0143"
- Description: Rapanea melanophloeos is traditionally used in South Africa in the treatment of ailments of the skin, pulmonary and gastro intestinal tract. This study was aimed at giving an overview of these traditional uses and comparing the phytochemicals and antibacterial activities of various crude extracts of the leaves, fruits and bark in order to validate these uses. The three plant parts were extracted using petroleum ether (PE), ethyl acetate (EtOAc), methanol (MeOH) and water. Various phytochemicals were compared using TLC, while alcohol precipitable solids (APS), non-polar terpenes and amino acids were analysed by GC-MS. Antibacterial activity was determined against three Gram-positive and three Gram-negative strains by microdilution assays. Caryophyllene oxides, α-cadinol and (−)-spathulenol were identified in the PE extracts. All nine essential amino acids were present in fruit extracts in significantly higher levels than in the leaves and bark; 255.1, 23.4 and 21.3 mg/g respectively. Most of the extracts showed good antibacterial activity, especially against the Gram-positive pathogens (MIC of ≤1 mg/mL), the EtOAc extracts exhibited the best activity with the fruit having an MIC values of 0.1 ± 0.2 mg/mL against Staphylococcus epidermidis and Enterococcus faecalis, 0.05 mg/mL against Bacillus cereus. Results from this study validate the ethnomedicinal uses of R. melanophloeos extracts for ailments of bacterial etiology. The plant had a rich supply of secondary metabolites, APS and amino acids and TLC and antibacterial activities of the extracts showed slight variations in chemical composition due to geographic distribution.
- Full Text:
- Date Issued: 2021
- Authors: Lukhele, Thabile , Olivier, Denise , Tata, Charlotte , Ikhile, Monisola I , Krause, Rui W M , van Vuuren, Sandy , Ndineh, Derek T
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/191791 , vital:45164 , xlink:href="https://doi.org/10.1515/psr-2020-0143"
- Description: Rapanea melanophloeos is traditionally used in South Africa in the treatment of ailments of the skin, pulmonary and gastro intestinal tract. This study was aimed at giving an overview of these traditional uses and comparing the phytochemicals and antibacterial activities of various crude extracts of the leaves, fruits and bark in order to validate these uses. The three plant parts were extracted using petroleum ether (PE), ethyl acetate (EtOAc), methanol (MeOH) and water. Various phytochemicals were compared using TLC, while alcohol precipitable solids (APS), non-polar terpenes and amino acids were analysed by GC-MS. Antibacterial activity was determined against three Gram-positive and three Gram-negative strains by microdilution assays. Caryophyllene oxides, α-cadinol and (−)-spathulenol were identified in the PE extracts. All nine essential amino acids were present in fruit extracts in significantly higher levels than in the leaves and bark; 255.1, 23.4 and 21.3 mg/g respectively. Most of the extracts showed good antibacterial activity, especially against the Gram-positive pathogens (MIC of ≤1 mg/mL), the EtOAc extracts exhibited the best activity with the fruit having an MIC values of 0.1 ± 0.2 mg/mL against Staphylococcus epidermidis and Enterococcus faecalis, 0.05 mg/mL against Bacillus cereus. Results from this study validate the ethnomedicinal uses of R. melanophloeos extracts for ailments of bacterial etiology. The plant had a rich supply of secondary metabolites, APS and amino acids and TLC and antibacterial activities of the extracts showed slight variations in chemical composition due to geographic distribution.
- Full Text:
- Date Issued: 2021
Evaluating and reflecting on coproduction of protected area management plans
- Roux, Dirk J, Nel, Jeanne L, Freitag, Stefanie, Novellie, Peter, Rosenberg, Eureta
- Authors: Roux, Dirk J , Nel, Jeanne L , Freitag, Stefanie , Novellie, Peter , Rosenberg, Eureta
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/370550 , vital:66353 , xlink:href="https://doi.org/10.1111/csp2.542"
- Description: Protected areas are complex social-ecological systems, hence their management should be guided by engagement and co-learning with diverse stakeholders. The challenge of effective stakeholder participation has generated a body of literature on the design and facilitation of coproduction processes. In this study, we used this literature to develop a principle-based framework for assessing coproduction. We then applied this framework to evaluate how well “adaptive planning” (a sub-process of adaptive management used for visioning and objective setting with stakeholders), as applied to the Garden Route National Park in South Africa, aligned with the ideals of coproduction. Our analysis revealed shortcomings in the adaptive planning process, which could be improved through broadening the agenda beyond the mandate and control of national parks, empowering collective agency among a wider stakeholder network, and embedding co-learning with stakeholders as an ongoing journey. A significant finding was that adaptive management does not align well with the ideals of coproduction, which may be better supported by an adaptive comanagement approach. The latter is particularly necessary in complex national parks that are diverse in terms of both ecosystems and stakeholders, and where governance may be contested.
- Full Text:
- Date Issued: 2021
- Authors: Roux, Dirk J , Nel, Jeanne L , Freitag, Stefanie , Novellie, Peter , Rosenberg, Eureta
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/370550 , vital:66353 , xlink:href="https://doi.org/10.1111/csp2.542"
- Description: Protected areas are complex social-ecological systems, hence their management should be guided by engagement and co-learning with diverse stakeholders. The challenge of effective stakeholder participation has generated a body of literature on the design and facilitation of coproduction processes. In this study, we used this literature to develop a principle-based framework for assessing coproduction. We then applied this framework to evaluate how well “adaptive planning” (a sub-process of adaptive management used for visioning and objective setting with stakeholders), as applied to the Garden Route National Park in South Africa, aligned with the ideals of coproduction. Our analysis revealed shortcomings in the adaptive planning process, which could be improved through broadening the agenda beyond the mandate and control of national parks, empowering collective agency among a wider stakeholder network, and embedding co-learning with stakeholders as an ongoing journey. A significant finding was that adaptive management does not align well with the ideals of coproduction, which may be better supported by an adaptive comanagement approach. The latter is particularly necessary in complex national parks that are diverse in terms of both ecosystems and stakeholders, and where governance may be contested.
- Full Text:
- Date Issued: 2021
Evaluating Community Engagement Strategies to Manage Stigma in Two African Genomics Studies Involving People Living with Schizophrenia or Rheumatic Heart Disease
- Campbell, Megan, Matshabane, Olivia P, Mqulwana, Sibonile, Mndini, Michael, Nagdee, Mohamed, Stein, Dan J, de Vries, Jantina
- Authors: Campbell, Megan , Matshabane, Olivia P , Mqulwana, Sibonile , Mndini, Michael , Nagdee, Mohamed , Stein, Dan J , de Vries, Jantina
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/302475 , vital:58199 , xlink:href="https://doi.org/10.1155/2021/9926495"
- Description: In global health research and genomics research specifically, community engagement has gained prominence in enhancing ethical conduct, particularly in managing the risk of stigmatization, but there is minimal scientific evidence on how to do this effectively. This article reports on community engagement evaluation strategies in two African genomics studies: the Stigma in African Genomics Research study and the Genomics of Schizophrenia in South African Xhosa People (SAX) study. Within the Stigma in African Genomics Research study, a self-report rating scale and open-ended questions were used to track participant responses to an experiential theatre workshop. The workshop focused on participant experiences of living with schizophrenia or rheumatic heart disease (RHD). While the schizophrenia group reported more alienation and less stigma resistance than the RHD group, both groups demonstrated increased stigma resistance over time, after participating in the workshops. Hearing from others living with and managing the same illness normalised participants’ own experiences and encouraged them. Within the SAX study, a short rating scale and qualitative feedback methods were used to evaluate a Mental Health Literacy Day targeting mental health stigma. Information talks about (i) the symptoms of schizophrenia and treatment options and (ii) the illness experiences of a patient in recovery were rated as the most helpful on the day. Audience members reported that these talks challenged negative perceptions about severe mental illness. Three important learnings emerged from these evaluations: firstly, integration of evaluation strategies at the research study planning phase is likely to promote more effective community engagement. Secondly, a combination of quantitative and qualitative methods that draw on simple descriptive statistics and thematic analysis can provide nuanced perspectives about the value of community engagement. Thirdly, such evidence is necessary in establishing and promoting the science of community engagement in genomics research and health research more broadly.
- Full Text:
- Date Issued: 2021
- Authors: Campbell, Megan , Matshabane, Olivia P , Mqulwana, Sibonile , Mndini, Michael , Nagdee, Mohamed , Stein, Dan J , de Vries, Jantina
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/302475 , vital:58199 , xlink:href="https://doi.org/10.1155/2021/9926495"
- Description: In global health research and genomics research specifically, community engagement has gained prominence in enhancing ethical conduct, particularly in managing the risk of stigmatization, but there is minimal scientific evidence on how to do this effectively. This article reports on community engagement evaluation strategies in two African genomics studies: the Stigma in African Genomics Research study and the Genomics of Schizophrenia in South African Xhosa People (SAX) study. Within the Stigma in African Genomics Research study, a self-report rating scale and open-ended questions were used to track participant responses to an experiential theatre workshop. The workshop focused on participant experiences of living with schizophrenia or rheumatic heart disease (RHD). While the schizophrenia group reported more alienation and less stigma resistance than the RHD group, both groups demonstrated increased stigma resistance over time, after participating in the workshops. Hearing from others living with and managing the same illness normalised participants’ own experiences and encouraged them. Within the SAX study, a short rating scale and qualitative feedback methods were used to evaluate a Mental Health Literacy Day targeting mental health stigma. Information talks about (i) the symptoms of schizophrenia and treatment options and (ii) the illness experiences of a patient in recovery were rated as the most helpful on the day. Audience members reported that these talks challenged negative perceptions about severe mental illness. Three important learnings emerged from these evaluations: firstly, integration of evaluation strategies at the research study planning phase is likely to promote more effective community engagement. Secondly, a combination of quantitative and qualitative methods that draw on simple descriptive statistics and thematic analysis can provide nuanced perspectives about the value of community engagement. Thirdly, such evidence is necessary in establishing and promoting the science of community engagement in genomics research and health research more broadly.
- Full Text:
- Date Issued: 2021
Field-based ecological studies to assess prospective biological control agents for invasive alien plants: An example from giant rat's tail grass
- Sutton, Guy F, Canavan, Kim N, Day, Michael M, Paterson, Iain D
- Authors: Sutton, Guy F , Canavan, Kim N , Day, Michael M , Paterson, Iain D
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/423756 , vital:72091 , xlink:href="https://doi.org/10.1111/1365-2664.13834"
- Description: Biological control (biocontrol) of invasive alien plants is a widely utilised weed management tool. Prospective biocontrol agents are typically assessed through host specificity testing and pre-release efficacy studies performed in quarantine. However, rearing of the potential biocontrol agents and/or test plants is often difficult or impossible under quarantine conditions. Moreover, practitioners may attain laboratory artefacts in quarantine, which may result in the potential agent being needlessly rejected. Field-based studies in the weed's indigenous distribution could overcome these issues.
- Full Text:
- Date Issued: 2021
- Authors: Sutton, Guy F , Canavan, Kim N , Day, Michael M , Paterson, Iain D
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/423756 , vital:72091 , xlink:href="https://doi.org/10.1111/1365-2664.13834"
- Description: Biological control (biocontrol) of invasive alien plants is a widely utilised weed management tool. Prospective biocontrol agents are typically assessed through host specificity testing and pre-release efficacy studies performed in quarantine. However, rearing of the potential biocontrol agents and/or test plants is often difficult or impossible under quarantine conditions. Moreover, practitioners may attain laboratory artefacts in quarantine, which may result in the potential agent being needlessly rejected. Field-based studies in the weed's indigenous distribution could overcome these issues.
- Full Text:
- Date Issued: 2021
Flavonoids from the Genus Euphorbia
- Magozwi, Douglas K, Dinala, Mmabatho, Mokwana, Nthabiseng, Siwe-Noundou, Xavier, Krause, Rui W M, Sonopo, Molahleli, McGaw, Lyndy J, Augustyn, Wilma A, Tembu, Vuyelwa J
- Authors: Magozwi, Douglas K , Dinala, Mmabatho , Mokwana, Nthabiseng , Siwe-Noundou, Xavier , Krause, Rui W M , Sonopo, Molahleli , McGaw, Lyndy J , Augustyn, Wilma A , Tembu, Vuyelwa J
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/191736 , vital:45159 , xlink:href="https://doi.org/10.3390/ph14050428"
- Description: Plants of the genus Euphorbia are widely distributed across temperate, tropical and subtropical regions of South America, Asia and Africa with established Ayurvedic, Chinese and Malay ethnomedical records. The present review reports the isolation, occurrence, phytochemistry, biological properties, therapeutic potential and structure–activity relationship of Euphorbia flavonoids for the period covering 2000–2020, while identifying potential areas for future studies aimed at development of new therapeutic agents from these plants. The findings suggest that the extracts and isolated flavonoids possess anticancer, antiproliferative, antimalarial, antibacterial, anti-venom, anti-inflammatory, anti-hepatitis and antioxidant properties and have different mechanisms of action against cancer cells. Of the investigated species, over 80 different types of flavonoids have been isolated to date. Most of the isolated flavonoids were flavonols and comprised simple O-substitution patterns, C-methylation and prenylation. Others had a glycoside, glycosidic linkages and a carbohydrate attached at either C-3 or C-7, and were designated as d-glucose, l-rhamnose or glucorhamnose. The structure–activity relationship studies showed that methylation of the hydroxyl groups on C-3 or C-7 reduces the activities while glycosylation loses the activity and that the parent skeletal structure is essential in retaining the activity. These constituents can therefore offer potential alternative scaffolds towards development of new Euphorbia-based therapeutic agents.
- Full Text:
- Date Issued: 2021
- Authors: Magozwi, Douglas K , Dinala, Mmabatho , Mokwana, Nthabiseng , Siwe-Noundou, Xavier , Krause, Rui W M , Sonopo, Molahleli , McGaw, Lyndy J , Augustyn, Wilma A , Tembu, Vuyelwa J
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/191736 , vital:45159 , xlink:href="https://doi.org/10.3390/ph14050428"
- Description: Plants of the genus Euphorbia are widely distributed across temperate, tropical and subtropical regions of South America, Asia and Africa with established Ayurvedic, Chinese and Malay ethnomedical records. The present review reports the isolation, occurrence, phytochemistry, biological properties, therapeutic potential and structure–activity relationship of Euphorbia flavonoids for the period covering 2000–2020, while identifying potential areas for future studies aimed at development of new therapeutic agents from these plants. The findings suggest that the extracts and isolated flavonoids possess anticancer, antiproliferative, antimalarial, antibacterial, anti-venom, anti-inflammatory, anti-hepatitis and antioxidant properties and have different mechanisms of action against cancer cells. Of the investigated species, over 80 different types of flavonoids have been isolated to date. Most of the isolated flavonoids were flavonols and comprised simple O-substitution patterns, C-methylation and prenylation. Others had a glycoside, glycosidic linkages and a carbohydrate attached at either C-3 or C-7, and were designated as d-glucose, l-rhamnose or glucorhamnose. The structure–activity relationship studies showed that methylation of the hydroxyl groups on C-3 or C-7 reduces the activities while glycosylation loses the activity and that the parent skeletal structure is essential in retaining the activity. These constituents can therefore offer potential alternative scaffolds towards development of new Euphorbia-based therapeutic agents.
- Full Text:
- Date Issued: 2021
Folic acid-modified phthalocyanine-nanozyme loaded liposomes for targeted photodynamic therapy
- Nwahara, Nnamdi, Abrahams, Garth, Prinsloo, Earl, Nyokong, Tebello
- Authors: Nwahara, Nnamdi , Abrahams, Garth , Prinsloo, Earl , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231369 , vital:49881 , xlink:href="https://doi.org/10.1016/j.pdpdt.2021.102527"
- Description: The hypoxic tumour microenvironment and poor spatiotemporal localization of photosensitizers are two significant obstacles that limit practical applications of photodynamic therapy. In response, a biocompatible, light-activatable liposome integrated with both a zinc phthalocyanine photodynamic component and Pt nanoparticles-decorated with MnO2 catalase-mimicking component are engineered. This multifunctional system was rationally designed using unsaturated phospholipids to achieve on-demand drug release following light irradiation. Specificity was achieved by folic acid functionalization resulting in folate-modified liposomes (FTLiposomes). We demonstrated its specific uptake by fluorescence imaging using folate receptor (FR) overexpressing HeLa and MCF-7 cells as in vitro models. This multifunctional liposome exhibits superior hypoxic anti-tumour effects and holds the potential to reduce side effects associated with untargeted therapy. Fluorescence of the constituent ZnPc and folate-receptor targeting could enable tracking and permit spatiotemporal regulation for improved cancer treatment.
- Full Text:
- Date Issued: 2021
- Authors: Nwahara, Nnamdi , Abrahams, Garth , Prinsloo, Earl , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231369 , vital:49881 , xlink:href="https://doi.org/10.1016/j.pdpdt.2021.102527"
- Description: The hypoxic tumour microenvironment and poor spatiotemporal localization of photosensitizers are two significant obstacles that limit practical applications of photodynamic therapy. In response, a biocompatible, light-activatable liposome integrated with both a zinc phthalocyanine photodynamic component and Pt nanoparticles-decorated with MnO2 catalase-mimicking component are engineered. This multifunctional system was rationally designed using unsaturated phospholipids to achieve on-demand drug release following light irradiation. Specificity was achieved by folic acid functionalization resulting in folate-modified liposomes (FTLiposomes). We demonstrated its specific uptake by fluorescence imaging using folate receptor (FR) overexpressing HeLa and MCF-7 cells as in vitro models. This multifunctional liposome exhibits superior hypoxic anti-tumour effects and holds the potential to reduce side effects associated with untargeted therapy. Fluorescence of the constituent ZnPc and folate-receptor targeting could enable tracking and permit spatiotemporal regulation for improved cancer treatment.
- Full Text:
- Date Issued: 2021
Force Field Parameters for Fe2+ 4S2− 4 Clusters of Dihydropyrimidine Dehydrogenase, the 5-Fluorouracil Cancer Drug Deactivation Protein: A Step towards In Silico Pharmacogenomics Studies
- Tendwa, Maureen B, Chebon-Bore, Lorna, Lobb, Kevin A, Musyoka, Thommas M, Taştan Bishop, Özlem
- Authors: Tendwa, Maureen B , Chebon-Bore, Lorna , Lobb, Kevin A , Musyoka, Thommas M , Taştan Bishop, Özlem
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451078 , vital:75016 , xlink:href="https://doi.org/10.3390/molecules26102929 "
- Description: The dimeric dihydropyrimidine dehydrogenase (DPD), metalloenzyme, an adjunct anti-cancer drug target, contains highly specialized 4 × Fe2+4S2−4 clusters per chain. These clusters facilitate the catalysis of the rate-limiting step in the pyrimidine degradation pathway through a harmonized electron transfer cascade that triggers a redox catabolic reaction. In the process, the bulk of the administered 5-fluorouracil (5-FU) cancer drug is inactivated, while a small proportion is activated to nucleic acid antimetabolites. The occurrence of missense mutations in DPD protein within the general population, including those of African descent, has adverse toxicity effects due to altered 5-FU metabolism. Thus, deciphering mutation effects on protein structure and function is vital, especially for precision medicine purposes. We previously proposed combining molecular dynamics (MD) and dynamic residue network (DRN) analysis to decipher the molecular mechanisms of missense mutations in other proteins. However, the presence of Fe2+4S2−4 clusters in DPD poses a challenge for such in silico studies. The existing AMBER force field parameters cannot accurately describe the Fe2+ center coordination exhibited by this enzyme. Therefore, this study aimed to derive AMBER force field parameters for DPD enzyme Fe2+ centers, using the original Seminario method and the collation features Visual Force Field Derivation Toolkit as a supportive approach. All-atom MD simulations were performed to validate the results. Both approaches generated similar force field parameters, which accurately described the human DPD protein Fe2+4S2−4 cluster architecture. This information is crucial and opens new avenues for in silico cancer pharmacogenomics and drug discovery related research on 5-FU drug efficacy and toxicity issues.
- Full Text:
- Date Issued: 2021
- Authors: Tendwa, Maureen B , Chebon-Bore, Lorna , Lobb, Kevin A , Musyoka, Thommas M , Taştan Bishop, Özlem
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451078 , vital:75016 , xlink:href="https://doi.org/10.3390/molecules26102929 "
- Description: The dimeric dihydropyrimidine dehydrogenase (DPD), metalloenzyme, an adjunct anti-cancer drug target, contains highly specialized 4 × Fe2+4S2−4 clusters per chain. These clusters facilitate the catalysis of the rate-limiting step in the pyrimidine degradation pathway through a harmonized electron transfer cascade that triggers a redox catabolic reaction. In the process, the bulk of the administered 5-fluorouracil (5-FU) cancer drug is inactivated, while a small proportion is activated to nucleic acid antimetabolites. The occurrence of missense mutations in DPD protein within the general population, including those of African descent, has adverse toxicity effects due to altered 5-FU metabolism. Thus, deciphering mutation effects on protein structure and function is vital, especially for precision medicine purposes. We previously proposed combining molecular dynamics (MD) and dynamic residue network (DRN) analysis to decipher the molecular mechanisms of missense mutations in other proteins. However, the presence of Fe2+4S2−4 clusters in DPD poses a challenge for such in silico studies. The existing AMBER force field parameters cannot accurately describe the Fe2+ center coordination exhibited by this enzyme. Therefore, this study aimed to derive AMBER force field parameters for DPD enzyme Fe2+ centers, using the original Seminario method and the collation features Visual Force Field Derivation Toolkit as a supportive approach. All-atom MD simulations were performed to validate the results. Both approaches generated similar force field parameters, which accurately described the human DPD protein Fe2+4S2−4 cluster architecture. This information is crucial and opens new avenues for in silico cancer pharmacogenomics and drug discovery related research on 5-FU drug efficacy and toxicity issues.
- Full Text:
- Date Issued: 2021
From introduction to nuisance growth: A review of traits of alien aquatic plants which contribute to their invasiveness
- Hussner, Andreas, Heidbuchel, Patrick, Coetzee, Julie A, Gross, Elisabeth M
- Authors: Hussner, Andreas , Heidbuchel, Patrick , Coetzee, Julie A , Gross, Elisabeth M
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/424006 , vital:72115 , xlink:href="https://doi.org/10.1007/s10750-020-04463-z"
- Description: Invasive alien aquatic plant species (IAAPs) cause serious ecological and economic impact and are a major driver of changes in aquatic plant communities. Their invasive success is influenced by both abiotic and biotic factors. Here, we summarize the existing knowledge on the biology of 21 IAAPs (four free-floating species, eight sediment-rooted, emerged or floating-leaved species, and nine sediment-rooted, submerged species) to highlight traits that are linked to their invasive success. We focus on those traits which were documented as closely linked to plant invasions, including dispersal and growth patterns, allelopathy and herbivore defence. The traits are generally specific to the different growth forms of IAAPs. In general, the species show effective dispersal and spread mechanisms, even though sexual and vegetative spread differs strongly between species. Moreover, IAAPs show varying strategies to cope with the environment. The presented overview of traits of IAAPs will help to identify potential invasive alien aquatic plants. Further, the information provided is of interest for developing species-specific management strategies and effective prevention measures.
- Full Text:
- Date Issued: 2021
- Authors: Hussner, Andreas , Heidbuchel, Patrick , Coetzee, Julie A , Gross, Elisabeth M
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/424006 , vital:72115 , xlink:href="https://doi.org/10.1007/s10750-020-04463-z"
- Description: Invasive alien aquatic plant species (IAAPs) cause serious ecological and economic impact and are a major driver of changes in aquatic plant communities. Their invasive success is influenced by both abiotic and biotic factors. Here, we summarize the existing knowledge on the biology of 21 IAAPs (four free-floating species, eight sediment-rooted, emerged or floating-leaved species, and nine sediment-rooted, submerged species) to highlight traits that are linked to their invasive success. We focus on those traits which were documented as closely linked to plant invasions, including dispersal and growth patterns, allelopathy and herbivore defence. The traits are generally specific to the different growth forms of IAAPs. In general, the species show effective dispersal and spread mechanisms, even though sexual and vegetative spread differs strongly between species. Moreover, IAAPs show varying strategies to cope with the environment. The presented overview of traits of IAAPs will help to identify potential invasive alien aquatic plants. Further, the information provided is of interest for developing species-specific management strategies and effective prevention measures.
- Full Text:
- Date Issued: 2021
Grand challenges in urban agriculture: ecological and social approaches to transformative sustainability
- Zimmerer, Karl S, Bell, Martha G, Chirisa, Innocent, Duvall, Chris S, Egerer, Monika, Hung, Po-Yi, Lerner, Amy M, Shackleton, Charlie M, Ward, James D, Ochoa, Carolina Y
- Authors: Zimmerer, Karl S , Bell, Martha G , Chirisa, Innocent , Duvall, Chris S , Egerer, Monika , Hung, Po-Yi , Lerner, Amy M , Shackleton, Charlie M , Ward, James D , Ochoa, Carolina Y
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/402287 , vital:69838 , xlink:href="https://doi.org/10.3389/fsufs.2021.668561"
- Description: This synopsis of the Grand Challenges of Urban Agriculture (UA) is framed by the urgent need to understand and strengthen the expanding yet highly diverse roles of UA amid rapid global urbanization, failures of predominant food systems, and crises in systems of physical and mental health. More than half of humanity lives in cities today and by 2030 this is projected to grow to 60.4 percent, ∼5 billion people (UN Habitat, 2020). More than 90 percent of urban demographic increase is anticipated to take place in the developing world. Ecological and social dimensions of UA are situated in these expanding spaces of cities, towns, and villages (along with their urban fringe or peri-urban areas), and among their diverse populations. UA is further situated in the powerful, far-reaching influences of urbanization processes that occur within and beyond these spaces. UA is thus integral to the prospect of Urban Sustainability as SDG 11 (“Make cities and human settlements inclusive, safe, resilient and sustainable”) of the U.N.’s 2030 Agenda for Sustainable Development.
- Full Text:
- Date Issued: 2021
- Authors: Zimmerer, Karl S , Bell, Martha G , Chirisa, Innocent , Duvall, Chris S , Egerer, Monika , Hung, Po-Yi , Lerner, Amy M , Shackleton, Charlie M , Ward, James D , Ochoa, Carolina Y
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/402287 , vital:69838 , xlink:href="https://doi.org/10.3389/fsufs.2021.668561"
- Description: This synopsis of the Grand Challenges of Urban Agriculture (UA) is framed by the urgent need to understand and strengthen the expanding yet highly diverse roles of UA amid rapid global urbanization, failures of predominant food systems, and crises in systems of physical and mental health. More than half of humanity lives in cities today and by 2030 this is projected to grow to 60.4 percent, ∼5 billion people (UN Habitat, 2020). More than 90 percent of urban demographic increase is anticipated to take place in the developing world. Ecological and social dimensions of UA are situated in these expanding spaces of cities, towns, and villages (along with their urban fringe or peri-urban areas), and among their diverse populations. UA is further situated in the powerful, far-reaching influences of urbanization processes that occur within and beyond these spaces. UA is thus integral to the prospect of Urban Sustainability as SDG 11 (“Make cities and human settlements inclusive, safe, resilient and sustainable”) of the U.N.’s 2030 Agenda for Sustainable Development.
- Full Text:
- Date Issued: 2021
Happy without money: Minimally monetized societies can exhibit high subjective well-being
- Miñarro, Sara, Reyes-García V, Aswani, Shankar, Selim, Samiya, Barrington-Leigh, Christopher P, Galbraith, Eric D
- Authors: Miñarro, Sara , Reyes-García V , Aswani, Shankar , Selim, Samiya , Barrington-Leigh, Christopher P , Galbraith, Eric D
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/403430 , vital:69960 , xlink:href="https://doi.org/10.1371/journal.pone.0244569"
- Description: Economic growth is often assumed to improve happiness for people in low income countries, although the association between monetary income and subjective well-being has been a subject of debate. We test this assumption by comparing three different measures of subjective well-being in very low-income communities with different levels of monetization. Contrary to expectations, all three measures of subjective well-being were very high in the least-monetized sites and comparable to those found among citizens of wealthy nations. The reported drivers of happiness shifted with increasing monetization: from enjoying experiential activities in contact with nature at the less monetized sites, to social and economic factors at the more monetized sites. Our results suggest that high levels of subjective well-being can be achieved with minimal monetization, challenging the perception that economic growth will raise life satisfaction among low income populations.
- Full Text:
- Date Issued: 2021
- Authors: Miñarro, Sara , Reyes-García V , Aswani, Shankar , Selim, Samiya , Barrington-Leigh, Christopher P , Galbraith, Eric D
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/403430 , vital:69960 , xlink:href="https://doi.org/10.1371/journal.pone.0244569"
- Description: Economic growth is often assumed to improve happiness for people in low income countries, although the association between monetary income and subjective well-being has been a subject of debate. We test this assumption by comparing three different measures of subjective well-being in very low-income communities with different levels of monetization. Contrary to expectations, all three measures of subjective well-being were very high in the least-monetized sites and comparable to those found among citizens of wealthy nations. The reported drivers of happiness shifted with increasing monetization: from enjoying experiential activities in contact with nature at the less monetized sites, to social and economic factors at the more monetized sites. Our results suggest that high levels of subjective well-being can be achieved with minimal monetization, challenging the perception that economic growth will raise life satisfaction among low income populations.
- Full Text:
- Date Issued: 2021
Higher temperatures are associated with reduced nestling body condition in a range restricted mountain bird
- Oswald, Krista N, Smit, Ben, Lee, Alan T K, Peng, Ceili L, Brock, Cameryn, Cunningham, Susan J
- Authors: Oswald, Krista N , Smit, Ben , Lee, Alan T K , Peng, Ceili L , Brock, Cameryn , Cunningham, Susan J
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/440547 , vital:73791 , https://doi.org/10.1111/jav.02756
- Description: Demonstrated negative effects of increased temperatures on avian reproductive success suggest a mechanism by which climate change may impact species persistence. High temperatures can result in reduced parental care and reduced nestling condition in passerines with dependent young, resulting in lowered fledging success and population recruitment. We examined provisioning rate and nestling condition in a South African mountain endemic, the Cape rockjumper Chaetops frenatus, whose population declines correlate with warming habitat. Our aim was to determine whether rockjumper reproductive success could be affected by high air temperatures. We set up video cameras on nests at three nestling age classes (≤ 7 days old; 8–12 days old; ≥ 13 days old) for 8 hours on 37 separate days.
- Full Text:
- Date Issued: 2021
- Authors: Oswald, Krista N , Smit, Ben , Lee, Alan T K , Peng, Ceili L , Brock, Cameryn , Cunningham, Susan J
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/440547 , vital:73791 , https://doi.org/10.1111/jav.02756
- Description: Demonstrated negative effects of increased temperatures on avian reproductive success suggest a mechanism by which climate change may impact species persistence. High temperatures can result in reduced parental care and reduced nestling condition in passerines with dependent young, resulting in lowered fledging success and population recruitment. We examined provisioning rate and nestling condition in a South African mountain endemic, the Cape rockjumper Chaetops frenatus, whose population declines correlate with warming habitat. Our aim was to determine whether rockjumper reproductive success could be affected by high air temperatures. We set up video cameras on nests at three nestling age classes (≤ 7 days old; 8–12 days old; ≥ 13 days old) for 8 hours on 37 separate days.
- Full Text:
- Date Issued: 2021
How people foraging in urban greenspace can mobilize social–ecological resilience during Covid-19 and beyond
- Sardeshpande, Mallika, Hurley, Patrick T, Mollee, Eefke, Garekae, Hesekia, Dahlberg, Annika C, Emery, Marla R, Shackleton, Charlie M
- Authors: Sardeshpande, Mallika , Hurley, Patrick T , Mollee, Eefke , Garekae, Hesekia , Dahlberg, Annika C , Emery, Marla R , Shackleton, Charlie M
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/402313 , vital:69841 , xlink:href="https://doi.org/10.3389/frsc.2021.686254"
- Description: Informal foraging for food and other natural materials in urban greenspaces is an activity undertaken by many across the world. For some, foraging is a necessary means of survival and livelihood, while for others, it provides cultural and recreational opportunities. In the socioeconomic crises induced by Covid-19, foraging can help communities, especially (but not exclusively) vulnerable people, cope with the impacts of lockdowns, and associated economic decline. In the long run, foraging can help improve social–ecological resilience in urban systems, particularly in response to climate, economic, and disease disruptions. First, we elaborate the ways in which urban foraging can provide immediate relief from the shocks to natural, human, social, physical, and financial capital. We then describe how over time, the livelihood, food, and income diversification brought about by foraging can contribute to preparedness for future uncertainties and gradual change. Cities are increasingly becoming home to the majority of humanity, and urban foraging can be one of the pathways that makes cities more liveable, for humans as well as other species we coexist with. Through the capitals framework, we explore the role foraging could play in addressing issues of biodiversity conservation, culture, and education, good governance and social justice, multifunctional greenspace, and sustainable nature-based livelihoods in urban areas.
- Full Text:
- Date Issued: 2021
- Authors: Sardeshpande, Mallika , Hurley, Patrick T , Mollee, Eefke , Garekae, Hesekia , Dahlberg, Annika C , Emery, Marla R , Shackleton, Charlie M
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/402313 , vital:69841 , xlink:href="https://doi.org/10.3389/frsc.2021.686254"
- Description: Informal foraging for food and other natural materials in urban greenspaces is an activity undertaken by many across the world. For some, foraging is a necessary means of survival and livelihood, while for others, it provides cultural and recreational opportunities. In the socioeconomic crises induced by Covid-19, foraging can help communities, especially (but not exclusively) vulnerable people, cope with the impacts of lockdowns, and associated economic decline. In the long run, foraging can help improve social–ecological resilience in urban systems, particularly in response to climate, economic, and disease disruptions. First, we elaborate the ways in which urban foraging can provide immediate relief from the shocks to natural, human, social, physical, and financial capital. We then describe how over time, the livelihood, food, and income diversification brought about by foraging can contribute to preparedness for future uncertainties and gradual change. Cities are increasingly becoming home to the majority of humanity, and urban foraging can be one of the pathways that makes cities more liveable, for humans as well as other species we coexist with. Through the capitals framework, we explore the role foraging could play in addressing issues of biodiversity conservation, culture, and education, good governance and social justice, multifunctional greenspace, and sustainable nature-based livelihoods in urban areas.
- 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
Impact of axial ligation on photophysical and photodynamic antimicrobial properties of indium (III) methylsulfanylphenyl porphyrin complexes linked to silver-capped copper ferrite magnetic nanoparticles
- Makola, Collen L, Nyokong, Tebello, Amuhaya, Edith K
- Authors: Makola, Collen L , Nyokong, Tebello , Amuhaya, Edith K
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185942 , vital:44450 , xlink:href="https://doi.org/10.1016/j.poly.2020.114882"
- Description: Photodynamic antimicrobial chemotherapy (PACT) is a well-known technique used against bacteria that have developed resistance towards antibiotics. We herein report the synthesis, photophysical properties, and PACT activity of 2-hydroxypyridine axial ligated indium 5,10,15,20-tetrakis-(4-phenylmethylthio) porphyrin (3) and quaternized 2-hydroxypyridine axial ligated indium 5,10,15,20-tetrakis-(4-phenylmethylthio) porphyrin (4). The porphyrin complexes (3 and 4) were further linked to oleyamine (OLM)/oleic acid (OLA) capped Ag/CuFe2O4 and also 6-mercapto-1-hexanol functionalized (MCH-Ag/CuFe2O4) nanoparticles through silver - sulphur (Ag-S) and silver-nitrogen (Ag-N); self-assembly. The PACT studies were carried out using Staphylococcus aureus. While all the synthesized porphyrins demonstrated PACT activity, the quaternized complex and its conjugate showed the highest PACT activity with 0% cell viability after irradiation for 25 min, resulting in a log reduction of 8.31.
- Full Text:
- Date Issued: 2021
- Authors: Makola, Collen L , Nyokong, Tebello , Amuhaya, Edith K
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185942 , vital:44450 , xlink:href="https://doi.org/10.1016/j.poly.2020.114882"
- Description: Photodynamic antimicrobial chemotherapy (PACT) is a well-known technique used against bacteria that have developed resistance towards antibiotics. We herein report the synthesis, photophysical properties, and PACT activity of 2-hydroxypyridine axial ligated indium 5,10,15,20-tetrakis-(4-phenylmethylthio) porphyrin (3) and quaternized 2-hydroxypyridine axial ligated indium 5,10,15,20-tetrakis-(4-phenylmethylthio) porphyrin (4). The porphyrin complexes (3 and 4) were further linked to oleyamine (OLM)/oleic acid (OLA) capped Ag/CuFe2O4 and also 6-mercapto-1-hexanol functionalized (MCH-Ag/CuFe2O4) nanoparticles through silver - sulphur (Ag-S) and silver-nitrogen (Ag-N); self-assembly. The PACT studies were carried out using Staphylococcus aureus. While all the synthesized porphyrins demonstrated PACT activity, the quaternized complex and its conjugate showed the highest PACT activity with 0% cell viability after irradiation for 25 min, resulting in a log reduction of 8.31.
- Full Text:
- Date Issued: 2021
Implementing a Content-Based Routing Framework for Application Integration on to Teleweaver Application Server
- Ngwenya, Sikhumbuzo, Shibeshi, Zelalem S, Terzoli, Alfredo
- Authors: Ngwenya, Sikhumbuzo , Shibeshi, Zelalem S , Terzoli, Alfredo
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430580 , vital:72701 , https://ieeexplore.ieee.org/abstract/document/9576969
- Description: This paper presents an architectural overview of content-based dynam-ic routing for integrating applications on to an application server named TeleWeaver, a middleware platform developed within Siyakhula Living Lab (SLL). SLL is an ICT4D project in the Eastern Cape Province of South Africa. TeleWeaver was created as a mediation layer between software systems developed for use by beneficiaries of the Siyakhula Living Lab. The main challenge with these disparate systems was that they had unnecessary, redundant components; TeleWeaver acts as a common platform that suits the development of many services such as eGovernment, eHealth, and eJudiciary.
- Full Text:
- Date Issued: 2021
- Authors: Ngwenya, Sikhumbuzo , Shibeshi, Zelalem S , Terzoli, Alfredo
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430580 , vital:72701 , https://ieeexplore.ieee.org/abstract/document/9576969
- Description: This paper presents an architectural overview of content-based dynam-ic routing for integrating applications on to an application server named TeleWeaver, a middleware platform developed within Siyakhula Living Lab (SLL). SLL is an ICT4D project in the Eastern Cape Province of South Africa. TeleWeaver was created as a mediation layer between software systems developed for use by beneficiaries of the Siyakhula Living Lab. The main challenge with these disparate systems was that they had unnecessary, redundant components; TeleWeaver acts as a common platform that suits the development of many services such as eGovernment, eHealth, and eJudiciary.
- Full Text:
- Date Issued: 2021