5-Fu inclusion complex capped gold nanoparticles for breast cancer therapy
- Authors: Lakkakula, Jaya R , Krause, Rui W M , Divakaran, Deepika , Barage, Sagar , Srivastava, Rohit
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/191713 , vital:45150 , xlink:href="https://doi.org/10.1016/j.molliq.2021.117262"
- Description: We have attempted to prolong the circulation time and increase the solubility of 5-Fluorouracil by complexing it with cyclodextrin and then further conjugating onto the gold nanoparticle to form 5Fu ICAu. The 1H NMR and molecular docking studies suggested that 5-Fu was included within the 2HP-β-CD cavity and H-5 proton probably serves as the binding site for stabilization of the inclusion complex. The 5Fu-ICAu showed higher cell inhibition rate when studied on MDA-MB-231 and MCF-7 breast cancer cell lines due to the enhanced permeability and retention (EPR) effect by allowing the selective accumulation of nanoparticles at tumor site. This unique system can serve as a novel nanocarrier for delivery of hydrophobic drugs.
- Full Text:
- Date Issued: 2021
A case for ethical frameworks to enhance mobile government implementation at South African municipalities
- Authors: Makwembere, Sandra , Garidzira, Rufaro
- Date: 2021
- Subjects: Government Ethics Technology and state Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7170 , vital:53081 , xlink:href="https://doi.org/10.4102/td.v17i1.826"
- Description: Interest in mobile government (m-government) is growing globally. Mobile government refers to the use of wireless and mobile technologies to deliver services to citizens, businesses, employees and other government entities. Presently, technological advancements take place despite questions on whether the existing policy and regulatory frameworks are suitable to regulate the effects of m-government. With m-government, municipal operations take place in virtual spaces where the consequences of such operations are still largely unknown and the frameworks that are apt to minimise any long-term effects on society are yet to be defined. This conceptual article suggests that ethical frameworks should be encouraged as part of mobile government implementation in municipalities to encourage reflective municipal practices and to improve judgement and behaviour in m-government decision-making. It contributes to debates on approaches to comprehensively support and guide mobile government towards positive municipal service delivery outcomes. Keywords: m-government; ethics; ethical frameworks; municipal service delivery; e-government; mobile technology
- Full Text:
- Date Issued: 2021
A Critical Review of Environmental Governance, Land Restitution, and Tourism in Protected Areas
- Authors: Ramukumba, Takalani
- Date: 2021
- Subjects: Tourism Land use Environmental protection Wildlife conservation Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7029 , vital:52756 , xlink:href=":https://doi.org/10.46222/ajhtl.19770720.200"
- Description: Natural areas, when protected, conserve the natural environment and function as social spaces in which tourism brings increased income, employment, and financial support for conservation. The inclusion of local community members in the planning and management of protected areas has been on the rise since the early 1900s. Tourism has been advocated as a strategy that can help in achieving economic development, especially in rural areas. However, governance issues and potential negative impacts of tourism development have been under inspection. Conservation efforts in Southern Africa especially in the late 1800s and early 1900s had negative impacts on the local communities since this led to many communities being displaced or having limited access to these protected areas. This has seen the need for ways and efforts to get local community members' despondency and attitudes towards protected areas change such that in the 20th century, there were efforts to use conservation models that included community members in the decision-making and benefit-sharing process to garner their support for protected areas. This paper reviews literature on environmental governance, land restitution in protected areas, tourism in protected areas, co-management, and the importance of community participation. These concepts are reviewed using Manyeleti Game Reserve as a case study. Keywords: Tourism, land restitution, environmental governance, wildlife resources, and stakeholder participation
- Full Text:
- Date Issued: 2021
A decade of biological control of Parthenium hysterophorus L.(Asteraceae) in South Africa reviewed: introduction of insect agents and their status
- Authors: Strathie, L W , Cowie, Blair W , McConnachie, Andrew J , Chidawanyika, Frank , Musedeli, Jufter N , Sambo, SMC , Magoso, EX , Gareeb, M
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/416795 , vital:71386 , xlink:href="https://hdl.handle.net/10520/ejc-ento_v29_n3_a11"
- Description: The annual herb, Parthenium hysterophorus L. (Asteraceae: Heliantheae) is a severe terrestrial invader globally. Infestations reduce crop yield, limit available grazing, hinder conservation efforts, and affect human and animal health in Africa, Asia and Australia, and on associated islands. Due to the impact and threat of further invasion of P. hysterophorus, a biological control (biocontrol) programme was initiated in 2003 in South Africa. This review discusses the research and implementation activities undertaken on the insect agents from 2011 to 2020. During this period, the stem-boring weevil Listronotus setosipennis Hustache (Coleoptera: Curculionidae), leaf-feeding beetle Zygogramma bicolorata Pallister (Coleoptera: Chrysomelidae) and seed-feeding weevil Smicronyx lutulentus Dietz (Coleoptera: Curculionidae), were found to be host specific and approved for release. Releases of mass-reared insect agents have been concentrated particularly in north-eastern South Africa, where P. hysterophorus infestations are most prolific. Post-release monitoring studies indicated localised establishment and impact of L. setosipennis and S. lutulentus. Listronotus setosipennis persisted through severe drought conditions, and although it disperses slowly, larval feeding is structurally damaging. Establishment of S. lutulentus is improving, reducing seed production where it is established. Zygogramma bicolorata resulted in defoliation at a few sites, but establishment has been poor and the beetle has been absent since 2019. Although a combination of fungal and insect agents were demonstrated to reduce P. hysterophorus, additional natural enemies could improve control. Consequently, the stem-galling moth Epiblema strenuana Walker (Lepidoptera: Tortricidae) and root-crown boring moth Carmenta sp. nr. ithacae (Beutenmüller) (Lepidoptera: Sesiidae) remain under evaluation. The management of P. hysterophorus in South Africa has been guided by the development of a national strategy, which incorporates multiple management methods, including biocontrol. International collaborations have intensified as a growing number of countries begin to utilize biocontrol to manage P. hysterophorus. Despite the progress towards biocontrol of P. hysterophorus during this period, increased utilisation of approved agents and the introduction of additional agents are necessary to achieve greater control.
- Full Text:
- Date Issued: 2021
A framework to test South Africa’s readiness for the fourth industrial revolution
- Authors: Olaitan, Olutoyin O. , Issah, Moshood , Wayi, Ntombovuyo
- Date: 2021
- Subjects: Industry 4.0 Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7153 , vital:53072 , xlink:href=" https://doi.org/10.4102/sajim.v23i1.1284"
- Description: Background: The fourth industrial revolution (4IR) is being touted as having the capacity to lift South Africa out of the challenges of poverty, unemployment and inequitable distribution of wealth. However, the state of the country’s readiness for the enabling technologies of the 4IR is in question. Objective: This article sought to investigate South Africa’s state of readiness for the technologies that enable the 4IR. The article proposed a framework which can be used to measure the country’s level of preparedness and implement the necessary processes to move the country into the 4IR era. Method: A detailed analysis of literature was carried out on the current and futuristic technologies employed by developed countries as they moved towards the 4IR. The fit – viability and the task – technology theories were employed to propose a framework to government for measuring its state of readiness for the 4IR in South Africa. Results: Based on findings from the literature study, the article proposed the 4IR readiness framework for government to measure and subsequently plans its response to the advent of 4IR technologies in the country. Conclusion: The framework revealed that South Africa has low technological capability, plummeting economic complexity and a fall in digital technological readiness. There is also a dearth of skilled workforce and technological infrastructure. It was recommended that government should focus on building and strengthening the resilience of both public and private institutions, investment in relevant 4IR education, infrastructural improvement, and promulgation and enforcement of legal framework to ensure security and privacy of data. Keywords: 4IR; task – technology; fit – viability; digital technology readiness; economic complexity
- Full Text:
- Date Issued: 2021
A heavy-atom-free π-extended N-confused porphyrin as a photosensitizer for photodynamic therapy
- Authors: Babu, Balaji , Mack, John , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185909 , vital:44447 , xlink:href="https://doi.org/10.1039/d1nj00112d"
- Description: The synthesis and characterization of a novel 1,3-diethyl-2-thiobarbituric-acid-substituted N-confused porphyrin (NCP-TB) is reported, along with a study of its photodynamic activity against MCF-7 cells using 530 (110 mW cm−2) and 660 nm (280 mW cm−2) Thorlabs light-emitting diodes for 30 min. The singlet oxygen quantum yield for NCP-TB is 0.38 compared to 0.23 for the parent unsubstituted N-confused porphyrin (NCP) due to the presence of a sulfur atom. NCP-TB exhibits enhanced PDT activity compared to NCP at both wavelengths. A significantly lower IC50 value of 5.2 μM was obtained at 530 nm (14.7 μM at 660 nm) despite a smaller light dose, due to a large red shift of the intense B band into the green region of the spectrum. 2′,7′-Dichlorofluorescein diacetate (DCFDA) assays demonstrate that there is intracellular generation of reactive oxygen species upon exposure to light.
- Full Text:
- Date Issued: 2021
A new species of Buyisa Distant, 1907 (Hemiptera Cicadidae Cicadettinae Cicadettini) from South Africa
- Authors: Sanborn, Allen F , Villet, Martin H
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441318 , vital:73877 , https://doi.org/10.4289/0013-8797.123.1.199
- Description: A new species of the cicada genus Buyisa Distant, 1907 is described from South Africa for an undetermined species referenced in the literature. Buyisa eccaensis new species is described and illustrated and notes on its biology are provided. A key to the officially described species of Buyisa is also included.
- Full Text:
- Date Issued: 2021
A population genetics study of Pale-winged Starlings, Onychognathus nabouroup, using novel microsatellite markers
- Authors: Munshi, Naadhira , Symes, Craig , Maayer, Pieter de , Craig, Adrian J F K , Henry, Laurence , Hausberger, Martine , Mollett, Jean
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448718 , vital:74754 , https://www.ajol.info/index.php/scopus/article/view/211291
- Description: Recent research into starling species has revealed the existence of vocal social markers and a link between song temporal structuring and social organisation. The aim of the present study was to develop a genetic tool for understanding the population structuring and behaviour (social/parental transmission) and mating in Pale-winged Starlings (Onychognathus nabouroup), a songbird which is found in arid areas of southern Africa. Using next-generation sequencing, microsatellite markers comprising six dinucleotides, eighteen trinucleotides and twenty-four tetra-nucleotides specific to the Pale-winged Starling were isolated and developed. A total of 77 birds were sampled from the Augrabies Falls Nature Reserve in South Africa (n= 53) and the Ai Ais-Richtersveld Transfrontier Park resort in Namibia (n= 24), respectively. Fifteen polymorphic microsatellite markers were genotyped. The statistical programme STRUCTURE revealed four different genetic clusters within the two populations.
- Full Text:
- Date Issued: 2021
A review of the biocontrol programmes against aquatic weeds in South Africa
- Authors: Coetzee, Julie A , Bownes, Angela , Martin, Grant D , Miller, Benjamin E , Smith, Rosalie , Weyl, Philip S R , Hill, Martin P
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/406965 , vital:70326 , xlink:href="https://hdl.handle.net/10520/ejc-ento_v29_n3_a18"
- Description: Biological control (biocontrol) against invasive macrophytes is one of the longest standing programmes in South Africa, initiated in the 1970s against water hyacinth, Pontederia crassipes Mart. (Pontederiaceae). Since then, 15 agent species (13 insects, one mite and one pathogen) have been released against six weeds, most of which are floating macrophytes, with excellent levels of success. The release of the water hyacinth planthopper Megamelus scutellaris Berg (Hemiptera: Delphacidae) in particular, has improved biocontrol prospects for water hyacinth since 2018. In the last decade, however, a new suite of submerged and rooted emergent invasive macrophytes has been targeted. The first release against a submerged macrophyte in South Africa, and the first release against Brazilian waterweed, Egeria densa Planch. (Hydrocharitaceae), anywhere in the world, was achieved with the release of a leafmining fly, Hydrellia egeriae Rodrigues-Júnior, Mathis and Hauser (Diptera: Ephydridae). Yellow flag, Iris pseudacorus L. (Iridaceae) and Mexican waterlily, Nymphaea mexicana Zucc. (Nymphaeaceae), have also been targeted for biocontrol for the first time worldwide, and are in the early stages of agent development. Post-release evaluations, long term monitoring and controlled experiments have highlighted the need for a more holistic approach to managing aquatic invasive plants in South Africa, whose presence is largely driven by eutrophication, resulting in regime shifts between floating and submerged invaded states.
- Full Text:
- Date Issued: 2021
Accelerated implementations of the RIME for DDE calibration and source modelling
- Authors: Van Staden, Joshua
- Date: 2021
- Subjects: Radio astronomy , Radio inferometers , Radio inferometers -- Calibration , Radio astronomy -- Data processing , Radio inferometers -- Data processing , Radio inferometers -- Calibration -- Data processing
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/172422 , vital:42199
- Description: Second- and third-generation calibration methods filter out subtle effects in interferometer data, and therefore yield significantly higher dynamic ranges. The basis of these calibration techniques relies on building a model of the sky and corrupting it with models of the effects acting on the sources. The sensitivities of modern instruments call for more elaborate models to capture the level of detail that is required to achieve accurate calibration. This thesis implements two types of models to be used in for second- and third-generation calibration. The first model implemented is shapelets, which can be used to model radio source morphologies directly in uv space. The second model implemented is Zernike polynomials, which can be used to represent the primary beam of the antenna. We implement these models in the CODEX-AFRICANUS package and provide a set of unit tests for each model. Additionally, we compare our implementations against other methods of representing these objects and instrumental effects, namely NIFTY-GRIDDER against shapelets and a FITS-interpolation method against the Zernike polynomials. We find that to achieve sufficient accuracy, our implementation of the shapelet model has a higher runtime to that of the NIFTY-GRIDDER. However, the NIFTY-GRIDDER cannot simulate a component-based sky model while the shapelet model can. Additionally, the shapelet model is fully parametric, which allows for integration into a parameterised solver. We find that, while having a smaller memory footprint, our Zernike model has a greater computational complexity than that of the FITS-interpolated method. However, we find that the Zernike implementation has floating-point accuracy in its modelling, while the FITS-interpolated model loses some accuracy through the discretisation of the beam.
- Full Text:
- Date Issued: 2021
Adaptation and validation of a computerized neurocognitive battery in the Xhosa of South Africa
- Authors: Cobb, Scott J , Moore, Tyler M , Stein, Dan J , Pretorius, Adele , Zingela, Zukiswa , Nagdee, Mohammed , Ngqengelele, Linda , Campbell, Megan , Sibeko, Goodman , King, Mary C , McClellan, Jon M , Port, Allison M , Jackson, Chad , Ruparel, Kosha , Susser, Ezra , Gur, Ruben C
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/302439 , vital:58196 , xlink:href="https://doi.org/10.1037/neu0000742"
- Description: Objective: Large-scale studies have revolutionized biomedical research, and neurocognitive tests can help elucidate the biological basis of neuropsychiatric diseases. However, studies have predominantly been conducted in Western settings. We describe the development and validation of a computerized battery (PennCNB) with the Xhosa population of South Africa. Method: Individuals with schizophrenia (n = 525) and a normative comparison group (n = 744) were balanced on age, sex, education, and region. Participants provided blood samples, were assessed psychiatrically, and were administered a PennCNB translation to isiXhosa, including measures of executive functions, episodic memory, complex cognition, social cognition, and sensorimotor speed. Feasibility was examined with test completion rates and input from administrators, and psychometric structural validity and associations with clinical and demographic characteristics were examined. Results: Tests were well tolerated by participants, as >87% had one (or fewer) test missing. Results suggested a similar factor structure to prior PennCNB studies in Western contexts, and expected age and sex effects were apparent. Furthermore, a similar profile of schizophrenia was observed, with neurocognitive deficits most pronounced for executive functions, especially attention, as well as memory, social cognition, and motor speed relative to complex cognition and sensorimotor speed. Conclusions: Results support the feasibility of implementing a culturally adapted computerized neurocognitive battery in sub-Saharan African settings and provide evidence supporting the concurrent validity of the translated instrument. Thus, the PennCNB is implementable on a large scale in non-Western contexts, shows expected factor structure, and can detect cognitive deficits associated with neuropsychiatric disorders. Obtaining valid measures of cognition by nonspecialized proctors is especially suitable in resource-limited settings, where traditional testing is prohibitive. Future work should establish normative standards, test–retest reliability, and sensitivity to treatment.
- Full Text:
- Date Issued: 2021
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
- 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
Advances in the regulation of weed biological control in South Africa
- Authors: Ivey, Philip J , Hill, Martin P , Zachariades, Costas
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/416819 , vital:71388 , xlink:href="https://hdl.handle.net/10520/ejc-ento_v29_n3_a24"
- Description: Regulation of biological control (biocontrol) is essential to ensure its continued safety and to enhance its acceptability as a key contributor to the management of damaging invasive alien plants in South Africa. Local researchers were concerned that regulators may become risk averse and over-cautious, thus preventing introductions of safe biocontrol agents, as bureaucratic impediments have contributed to the decline in the number of biocontrol releases in several other countries. In South Africa, the introduction of a transparent and inclusive review process has averted these concerns. Legislation in South Africa enables departments concerned with protecting environmental and agricultural resources, to work together to regulate potential risks. An interdepartmental committee, advised by independent specialists, facilitate the review of research into the safety of potential biocontrol agents. Regulators have reviewed and timeously assessed 26 potential biocontrol agents between 2013 and 2020. This has ensured that the considerable benefits from safe biocontrol agents are available for management of some of South Africa’s worst invasive alien plants. We review the system in South Africa and suggest possible improvements to the regulatory framework.
- Full Text:
- Date Issued: 2021
Advancing Assessment Thinking in Education for Sustainable Development with a Focus on Significant Learning Processes
- Authors: Shumba, Overson , Mandikonza, Caleb , Lotz-Sisitka, Heila
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/435209 , vital:73138 , ISBN 9781928502241 , https://library.oapen.org/handle/20.500.12657/64082
- Description: This position paper is developed in the context of the Fundisa [Teaching] for Change teacher education programme (www.fundisaforchange.co.za), as well as the Sustainability Starts with Teachers programmes for teacher education (www. sustainabilityteachers.org/course). Fundisa for Change is a South African programme while Sustainability Starts with Teachers is a Southern Africa Development Community (SADC) programme for teacher educators. Both these programmes seek to enhance transformative environments and sustainability education processes in teacher education. They have a strategic focus on situated and transformative learning approaches for learners to learn to ‘know the world’ and practice ‘being in the world’. The real world provides the context for learning and assessment for learning, but not enough is known about assessment of such learning.
- Full Text:
- Date Issued: 2021
Advancing urban ecology in the global south: emerging themes and future research directions
- Authors: du Toit, Marie J , Shackleton, Charlie M , Cilliers, Sarel S , Davoren, Elandre
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/433713 , vital:72996 , ISBN 978-3-030-67650-6 , https://doi.org/10.1007/978-3-030-67650-6_17
- Description: The rapid growth in urban ecological research and application has been led by countries of the Global North, particularly Europe and the USA, albeit not restricted to them. However, this belies that most urban growth is currently in the Global South, with the differential set to increase in the future. Thus, there is an imbalance between where the bulk of urban ecological research and framings are developed and where the majority of urban citizens globally live, work and seek to meet their aspirations. This chapter illustrates how this book addressed the identified research gaps in the Global South. We also highlight dominant recurring themes in Global South research discourse and importantly, where future research efforts over the next decade should be focussed. Eight themes are considered, namely: inequality; informality; urban–rural links; small and medium-sized towns and cities; urban green infrastructure, biodiversity and ecosystem services; understanding and accommodating multiple worldviews of urban nature; human health and urban nature; and specific research approaches.
- Full Text:
- Date Issued: 2021
Alcohol use during pregnancy: prevalence and patterns in selected Buffalo City areas, South Africa
- Authors: Macleod, Catriona I , Young, Charles S , Molokoe, Katlego C
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/443611 , vital:74137 , xlink:href="https://www.ajol.info/index.php/ajrh/article/view/205539"
- Description: The high rate of foetal alcohol spectrum disorders, which results from alcohol consumption during pregnancy, is of concern in South Africa. The aims of this research were to establish the prevalence, patterns and factors associated with alcohol use amongst pregnant women attending antenatal clinics in two former township areas of Buffalo City, South Africa. A survey was conducted using a structured questionnaire that included socio-demographic questions, and the Alcohol Use Test (AUDIT). The questionnaire was administered in English, Afrikaans or isiXhosa by healthcare providers trained in its administration. Consecutive sampling was used, with all willing women presenting at public clinics offering antenatal care in the two townships being invited to participate. Of the 18 clinics operating in the two townships, 16 were willing to participate, resulting in a sample of 1028 women over a nine-month period. Data were analysed in Medcalc using descriptive statistics, one-way analysis of variance, independent samples t-test and a multivariable binary logistic regression analysis. Two-thirds of the sample did not drink alcohol, but results showed high levels of risky alcohol use: 20.1% on the total AUDIT scale, and 16.8% on the AUDIT-C scale. The following variables were found to be significantly associated with risky drinking: age; race; report of intimate partner violence (IPV); and other regular drinker in the home. Employment status, education status, relationship status, parity and gestation were not associated with risky drinking. Interventions aimed at reducing alcohol use during pregnancy should address: drinking youth cultures; drinking norms within the home; and intimate partner violence. Future studies should include additional mental and physical health variables.
- Full Text:
- Date Issued: 2021
Aluminum corrosion retardation properties of acetamidophenoxy phthalocyanines: Effect of central metal
- Authors: Nnaji, Nnaemeka , Sen, Pinar , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185433 , vital:44386 , xlink:href="https://doi.org/10.1016/j.molstruc.2021.130806"
- Description: Corrosion inhibition performances and adsorption behaviour at the aluminum-HCl solution interface were investigated for metal free (2), ClGa (3) and Co (4) tetrakis (4-acetamidophenoxy) phthalocyanine. Electrochemical techniques were used in the study and complemented with Fourier transform infrared, scanning electron microscopy and X-ray diffraction measurements. Potentiodynamic polarization technique gave inhibition efficiency values as 93.3% (2), 69.7% (3) and 87.7% (4) at 28°C at highest inhibitor concentration (10 µM) in the following order 2 > 4 > 3. These compounds exhibited good corrosion inhibition performance as mixed-type corrosion inhibitors. All applied techniques gave results which corroborated.
- Full Text:
- Date Issued: 2021
Amphiphilic axially modified cationic indium-porphyrins linked to hydrophilic magnetic nanoparticles for photodynamic antimicrobial chemotherapy against gram-negative strain; Escherichia coli
- Authors: Makolla, Collen L , Mgidlana, Sithi , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185024 , vital:44317 , xlink:href="https://doi.org/10.1016/j.dyepig.2021.109262"
- Description: In this study, we report on the synthesis, characterization, and application of indium porphyrins linked to silver core-shell magnetic nanoparticles for in vitro photodynamic antimicrobial chemotherapy (PACT) against gram-negative strain, E. coli. This work compares the photophysicochemical and PACT activities of InCl 5-p-carboxyphenyl-10-15-20-(tris-4-methylpyridinium)-triiodide porphyrin (1), InCl 5-p-carboxyphenyl-10-15-20-(tris-4-hexylpyridinium)-triiodide porphyrin (2), In (para-aminophenyl) 5,10,15,20-tetrakis(4-methylpyridinium)-tetraiodide porphyrin (3), and In (para-aminophenyl) 5,10,15,20-tetrakis(4-hexylpyridinium)-tetraiodide porphyrin (4). The comparisons were based on the structure and number of charges. Hydrophilic and hydrophobic characters of the amphiphilic porphyrins were studied by comparing the effect of the different alkyl halides (iodomethane and iodohexane) quaternizing agents. The porphyrin complexes were further linked to magnetic nanoparticles to facilitate antimicrobial synergy and recovery of the complexes after use. High Log reduction values ranging from 7.19 to 9.58 were obtained for the quaternized complexes.
- Full Text:
- Date Issued: 2021
An Analysis of Employee Motivation in a Multinational Context in Sub Saharan Africa
- Authors: Acha-Anyi, Paul Nkemngu , Masaraure, Robson
- Date: 2021
- Subjects: Employee motivation Sub-Saharan Africa Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7021 , vital:52757 , xlink:href=":https://doi.org/10.46222/ajhtl.19770720-119"
- Description: This study assesses motivational preferences of employees in a multinational context in Sub Saharan Africa. Using the Grundfos group operating sites in Ghana, Kenya and South Africa as a case study, the study explores quantitative data on possible differences in employee motivational factors based on selected variables such as location, length of service and managerial status. Questionnaires were employed in collecting data from 131 participants from the three locations of Grundfos Sub Saharan Africa (SSA). Results of the study reveal that the factor “equal treatment of employees” is considered most important among the respondents. It is also noted that there were no significant statistical differences among the participants based on the examined variables. Policy and practical implications of the findings of this study are discussed, particularly around the development and implementation of Human resources policies that address employee perceptions of equity. This study makes a contribution to existing literature on employee motivation in multinational settings. Keywords: Employee motivation, motivational factors, multinational context, Sub-Saharan Africa
- Full Text:
- Date Issued: 2021
An Application to Support end-users of wi-fi Hotspots in the Township of Makhanda
- Authors: Buwa, Lubabalo , Shibeshi, Zelalem S , Terzoli, Alfredo
- Date: 2021
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429077 , vital:72558 , https://ieeexplore.ieee.org/abstract/document/9514200
- Description: Having access to the Internet is a powerful resource that can change one's life, but connectivity inequality continues to be a significant issue, especially for disadvantaged communities. The usage of Wi-Fi hotspots is becoming very useful for accommodating many people living in underprivileged areas to connect to the Internet. Primarily, these hotspots get deployed in public places like hotels, restaurants, etc. This paper discusses how such a system can be made to work as a solution for disadvantaged communities considering the user base in such communities and adhering to government regulations. The research is developed in collaboration with Khula Tech Solutions ISP that provides wireless Internet services in Makhanda (formally known as Grahamstown). Khula Tech Solutions is starting an initiative of installing Wi-Fi hotspots around the township of Makhanda and needs an application that will support users of the Wi-Fi hotspots. The research's result is a proof-of-concept mobile application developed through iterative and incremental software development techniques and mobile application technologies. With this research, the hope is that it is the beginning of further work for the users to become connected citizens.
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- Date Issued: 2021