List of Titles

Marine robots for coastal ocean research in the Western Indian Ocean

- Palmer, Matthew R, Shagude, Yohana W, Roberts, Michael J, Popva, Ekaterina, Wihsgott, Juliane U, Aswani, Shankar, Coupland, Jack, Howe, John A, Bett, Brian J, Osuka, Kennedy E, Abernethy, Colin, Alexiou, Sofia, Painter, Stuart C, Kamau, Joseph N, Nyandwi, Ntahondi, Sekadende, Baraka

Authors: Palmer, Matthew R , Shagude, Yohana W , Roberts, Michael J , Popva, Ekaterina , Wihsgott, Juliane U , Aswani, Shankar , Coupland, Jack , Howe, John A , Bett, Brian J , Osuka, Kennedy E , Abernethy, Colin , Alexiou, Sofia , Painter, Stuart C , Kamau, Joseph N , Nyandwi, Ntahondi , Sekadende, Baraka
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/403445 , vital:69962 , xlink:href="https://hdl.handle.net/10520/ejc-cristal-v10-n1-a7"
Description: Marine robots have the potential to enhance WIO marine research to improve regional adaptation to the challenges presented by climate change by providing enhanced research capacity that bypasses the requirement for expensive infrastructure, such as large research vessels. This paper tests this potential and assesses the readiness of WIO communities to adopt autonomous technologies to meet its marine research priorities. We apply a range of analyses to a marine robots case study undertaken in waters around the island of Pemba, part of the Zanzibar archipelago, in Tanzania in 2019. The campaign formed part of a multinational project focused on increasing WIO capacity to meet food security and ocean sustainability challenges. A community engagement programme with six Tanzanian coastal communities resulted in positive changes in attitudes towards marine robots with reported increases in understanding and acceptance of such technologies. Suspicion of the robots was reduced and a lower risk of removing operational equipment was recorded following the provision of educational material. Cost, risk and benefit analysis shows that marine robots are perceived to provide high level benefits, but come at a high cost that is difficult to achieve using national or regional funding. An assessment of the capacity of WIO marine institutes to adopt such technologies shows that prior to this work, few skills or infrastructure related to marine robots were available to researchers and further confirmed that funding opportunities were perceived to be largely unavailable at institutional, national, regional or international levels. Responses from regional partners following completion of the case study however, revealed an uplift in perceived capacity, particularly related to access to infrastructure and expertise as well as support and opportunities for funding at each level. The presented case study is shown to have been a valuable demonstrator of the benefits of using marine robots to meet WIO coastal ocean research requirements and regional capacity was shown to be substantially increased within the broad range of marine institutes surveyed throughout the case study period. This study demonstrates that taking early steps towards adopting marine autonomous robots has increased WIO regional marine research capacity and increased the confidence and willingness of local researchers to seek alternative solutions to ongoing marine research challenges. Recommendations for future action that will continue to increase the capacity and readiness for regional adoption of marine robots include investment at local, national and regional levels to provide accessible training opportunities and to facilitate regional and international collaborations; investment in a regional hub, or centre of excellence for marine robotic technology; early adoption of newly emerging smaller, cheaper autonomous technologies; investment in local skills and support facilities to aid local buy-in and acceptance while supporting regional capacity.
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Date Issued: 2022

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Measuring discrimination experienced by people with a mental illness

- Brohan, Elaine, Thornicroft, Graham, Rüsch, Nicolas, Lasalvia, Antonio, Campbell, Megan M, Yalçınkaya-Alkar, Özden, Lanfredi, Mariangela, Ochoa, Susana, Üçok, Alp, Tomás, Catarina, Fadipe, Babatunde, Sebes, Julia, Fiorillo, Andrea, Sampogna, Gaia, Paula, Cristiane Silvestre, Valverde, Leonadis, Schomerus, Georg, Klemm, Pia, Ouali, Uta, Castelein, Stynke, Alexová, Aneta, Oexle, Nathalie, Guimarães, Patrícia Neves, Sportel, Bouwina Esther, Chang, Chih-Cheng, Li, Jie, Shanthi, Chilasagaram, Reneses, Blanca, Bakolis, Ioannis, Evans-Lacko, Sarah

Authors: Brohan, Elaine , Thornicroft, Graham , Rüsch, Nicolas , Lasalvia, Antonio , Campbell, Megan M , Yalçınkaya-Alkar, Özden , Lanfredi, Mariangela , Ochoa, Susana , Üçok, Alp , Tomás, Catarina , Fadipe, Babatunde , Sebes, Julia , Fiorillo, Andrea , Sampogna, Gaia , Paula, Cristiane Silvestre , Valverde, Leonadis , Schomerus, Georg , Klemm, Pia , Ouali, Uta , Castelein, Stynke , Alexová, Aneta , Oexle, Nathalie , Guimarães, Patrícia Neves , Sportel, Bouwina Esther , Chang, Chih-Cheng , Li, Jie , Shanthi, Chilasagaram , Reneses, Blanca , Bakolis, Ioannis , Evans-Lacko, Sarah
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/302498 , vital:58202 , xlink:href="https://doi.org/10.1017/S0033291722000630"
Description: Background: The Discrimination and Stigma Scale (DISC) is a patient-reported outcome measure which assesses experiences of discrimination among persons with a mental illness globally. Methods: This study evaluated whether the psychometric properties of a short-form version, DISC-Ultra Short (DISCUS) (11-item), could be replicated in a sample of people with a wide range of mental disorders from 21 sites in 15 countries/territories, across six global regions. The frequency of experienced discrimination was reported. Scaling assumptions (confirmatory factor analysis, inter-item and item-total correlations), reliability (internal consistency) and validity (convergent validity, known groups method) were investigated in each region, and by diagnosis group. Results: 1195 people participated. The most frequently reported experiences of discrimination were being shunned or avoided at work (48.7%) and discrimination in making or keeping friends (47.2%). Confirmatory factor analysis supported a unidimensional model across all six regions and five diagnosis groups. Convergent validity was confirmed in the total sample and within all regions [ Internalised Stigma of Mental Illness (ISMI-10): 0.28–0.67, stopping self: 0.54–0.72, stigma consciousness: −0.32–0.57], as was internal consistency reliability (α = 0.74–0.84). Known groups validity was established in the global sample with levels of experienced discrimination significantly higher for those experiencing higher depression [Patient Health Questionnaire (PHQ)-2: p more than 0.001], lower mental wellbeing [Warwick-Edinburgh Well-being Scale (WEMWBS): p is less than 0.001], higher suicidal ideation [Beck Hopelessness Scale (BHS)-4: p is less than 0.001] and higher risk of suicidal behaviour [Suicidal Ideation Attributes Scale (SIDAS): p is less than 0.001]. Conclusions: The DISCUS is a reliable and valid unidimensional measure of experienced discrimination for use in global settings with similar properties to the longer DISC. It offers a brief assessment of experienced discrimination for use in clinical and research settings.
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Date Issued: 2022

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Methods for assessing the quality of AM fungal bio-fertilizer: Retrospect and future directions

- Agnihotri, R, Sharma, M P, Bucking, H, Dames, Joanna F, Bagyaraj, D J

Authors: Agnihotri, R , Sharma, M P , Bucking, H , Dames, Joanna F , Bagyaraj, D J
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/448626 , vital:74747 , https://doi.org/10.1007/s11274-022-03288-3
Description: In the recent past, the mass production of arbuscular mycorrhizal (AM) fungi has bloomed into a large biofertilizer industry. Due to their obligate symbiotic nature, these fungi are propagated on living roots in substrate-based pot cultures and RiTDNA in in vitro or root organ culture systems. The quality assessment of AM inocula remains critical for the production and efficacy evaluation of AM fungi. The vigour of AM inocula are assessed through microscopic methods such as inoculum potential, infectivity potential/infection units, most probable number (MPN) and spore density. These methods marginally depend on the researcher’s skill. The signature lipids specific to AM fungi, e.g. 16:1ω5cis ester-linked, phospholipid, and neutral lipid fatty acids provide more robustness and reproducibility. The quantitative real-time PCR of AM fungal taxa specific primers and probes analyzing gene copy number is also increasingly used. This article intends to sensitize AM fungal researchers and inoculum manufacturers to various methods of assessing the quality of AM inocula addressing their merits and demerits. This will help AM producers to fulfil the regulatory requirements ensuring the supply of high-quality AM inocula to end-users, and tap a new dimension of AM research in the commercial production of AM fungi and its application in sustainable plant production systems.
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Date Issued: 2022

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Mitigating Climate Change: The Influence of Arbuscular Mycorrhizal Fungi on Maize Production and Food Security

- Maússe-Sitoe, Silvia N D, Dames, Joanna F

Authors: Maússe-Sitoe, Silvia N D , Dames, Joanna F
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , book chapter
Identifier: http://hdl.handle.net/10962/453465 , vital:75256 , ISBN 978-1-83768-091-7 , https://www.intechopen.com/chapters/84486
Description: Anthropogenic activities have contributed to the increased atmospheric concentration of greenhouse gases, which are an important contributor to climate change. From 1940 to 2004, global emissions increased by 70%, and projections suggest a continual increase by 2050 due to agriculture, forestry, and other land uses. Arbuscular mycorrhizal (AM) fungi are ubiquitous in undisturbed soils and form a symbiotic relationship with various plants. The relationship that enhances nutrient uptake and plant growth, among other benefits, is well known. Several soil management practices employed in agriculture adversely affect the symbiosis. Zea mays (maize) provides 30% of total caloric intake to 4.5 billion people worldwide and is an important staple crop, vulnerable to climate change. Higher temperatures can result in increased water demand, while changes in precipitation can result in crop failure. AM fungi can be applied as inoculants to maize. Resulting in improved plant growth, yield, and nutrient uptake and providing superior food quality properties, such as increased antioxidants, vitamins, and minerals. AM fungi are considered a crucial biotechnological tool in crop production. This review illustrates their essential role in sustainable maize production and emphasizes the need to maintain AM fungal communities in the soil to mitigate the effects of climate change.
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Date Issued: 2022

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Mixed-species flocks of insectivorous birds (‘bird parties’) in Afrotropical forests and woodlands: a review

- Craig, Adrian J F K

Authors: Craig, Adrian J F K
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/449420 , vital:74820 , https://doi.org/10.2989/00306525.2022.2064930
Description: Mixed-species flocks of foraging insectivorous birds are found worldwide and have been best studied in the Neotropical region. A survey of the published literature reveals that mixed-species flocks (often termed ‘bird parties’) comprised of 2–30 species and sometimes >70 individual birds are regularly encountered in forest and woodland habitats throughout the Afrotropical region. On mainland Africa, >600 species representing 59 bird families have been reported in such flocks, and for at least 300 species foraging in such flocks may constitute an important part of their feeding activity. In Madagascar, >60 species of 19 families have been recorded in mixed-species flocks, with more than 40 species frequent participants. These foraging parties are dominated by gleaning and sallying insectivorous birds, with other feeding guilds represented by fewer species and individuals.
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Date Issued: 2022

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Neoliberalism’s conditioning effects on the university and the example of proctoring during COVID-19 and since

- McKenna, Sioux

Authors: McKenna, Sioux
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/426929 , vital:72401 , xlink:href="https://doi.org/10.1080/14767430.2022.2100612"
Description: Neoliberalism has shaped the academy in ways that constrain its potential as a public good. Neoliberalism is based on the assumption that, by submitting to the so-called neutral forces of the market, wealth can be created alongside the achievement of equality and efficiency. Although this assumption is demonstrably false, neoliberalism remains politically powerful. As an example, this article discusses how neoliberalism has enabled the rapid uptake of proctoring software during the covid pandemic and since. ‘Proctoring' is the online monitoring of students’ behaviour as they sit for exams. Many within the academy consider proctoring software to be dehumanizing – essentially legalized spyware. They argue that the software invades privacy and is inherently racist and ableist, amongst other things. It is hoped that by understanding how structural forces such as neoliberalism affect both our agency and university activities, frequently against the common good, strategies can be developed to change these structures.
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Date Issued: 2022

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Not there yet: knowledge building in educational development ten years on

- Boughey, Chrissie

Authors: Boughey, Chrissie
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/426954 , vital:72403 , xlink:href="https://doi.org/10.1080/13562517.2022.2121158"
Description: This paper responds to a question posed by [Shay, Suellen. 2012. “Educational Development as a Field: Are We There Yet?” Higher Education Research and Development 31 (3): 311–323. doii:10.1080/07294360.2011.631520] about the status of knowledge building in the field of Educational Development. In her paper, Shay critiques knowledge produced in the field arguing that it is ‘codified practice’ [Gamble, Jeanne. 2001. “Modelling the Invisible: The Pedagogy of Craft Apprenticeship.” Studies in Continuing Education 23 (2): 185–200. doii:10.1080/01580370120101957; Gamble, Jeanne. 2004. “Retrieving the General from the Particular: The Structure of Craft Knowledge.” In Reading Bernstein, Researching Bernstein, edited by J. Muller, B. Davies, and A. Morais, 189–203. Abingdon: Routledge; Gamble, Jeanne. 2006. “Theory and Practice in the Vocational Curriculum.” In Knowledge, Curriculum and Qualifications in South African Further Education, edited by M. Young and J. Gamble, 87–103. Pretoria: HSRC Press] rather than applied theory which could succeed in reconceptualising problems rather than simply trying to address them. This paper draws on a review of research produced in the field in recent years in South Africa to argue that, although some work does result in the reconceptualision of problems the higher education, it is limited in that (i) it has been produced by a relatively small group of practitioners located at a few universities and (ii) draws on theory developed in the Global North. The paper then proceeds to offer some tentative suggestions for the way future work aimed at knowledge building could proceed.
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Date Issued: 2022

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Novel cationic-chalcone phthalocyanines for photodynamic therapy eradication of S. aureus and E. coli bacterial biofilms and MCF-7 breast cancer

- Openda, Yolande Ikala, Babu, Balaji, Nyokong, Tebello

Authors: Openda, Yolande Ikala , Babu, Balaji , Nyokong, Tebello
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/300129 , vital:57895 , xlink:href="https://doi.org/10.1016/j.pdpdt.2022.102863"
Description: New tetrasubstituted zinc (II) and indium (III) phthalocyanines bearing dimethylamino chalcone group (complexes 3 and 4) as well as their quaternized analogs (3a and 4a) have been assessed for their photodynamic therapy (PDT) of cancer as well as photodynamic antimicrobial chemotherapy activities against biofilms and planktonic cultures of pathogenic bacteria of Staphylococcus aureus and Escherichia coli. Compared to the non-quaternized phthalocyanines 3 and 4, the cationic phthalocyanines 3a and 4a exhibit a higher photodynamic inactivation against the planktonic cells with log reduction values above 9 at a concentration of 1.25 µM. This was attributed to the positive charge which enhances cellular uptake. More interestingly, 3a and 4a show a higher photodynamic inactivation (less than 3% of S. aureus survived) on their biofilm counterparts thanks to their stronger affinity to these cells. 3a and 4a Pcs also exhibited interesting PDT activity against MCF-7 cancer cells giving IC50 values of 17.9 and 7.4 μM, respectively following 15 min irradiation. The obtained results in this work show that the positively charged phthalocyanines 3a and 4a are potential antibacterial photosensitizers that show some selectivity toward the Gram-positive and Gram-negative bacteria as well as MCF-7 breasts cancer cells.
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Date Issued: 2022

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One and done, or a bundle and stumble? an exploration of assessment methods in undergraduate science curricula

- Edwards, Shelley

Authors: Edwards, Shelley
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/461539 , vital:76211 , xlink:href="https://doi.org/10.2478/atd-2022-0023"
Description: Assessment, historically, has been done in a summative manner in post-secondary education (HE). Whilst useful for the purposes of grading and assessment of competency, there is also increasing pressure from post-secondary education institutions to meet certain standards in terms of education quality and graduate numbers, putting pressure on teachers to produce evidence of students’ level of understanding and thus putting a greater emphasis on the use of summative assessments. The formative assessment approach for student learning is preferable in some fields, but how useful is this format for the science subjects?
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Date Issued: 2022

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Online stories of inclusion and exclusion of learners with disabilities in South Africa

- Dalvit, Lorenzo

Authors: Dalvit, Lorenzo
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , book chapter
Identifier: http://hdl.handle.net/10962/468206 , vital:77030 , ISBN 978-84-09-45476-1 , doi: 10.21125/edulearn.2022.1378
Description: A quarter of a century since the end of apartheid, the education system in South Africa still reflects its legacy of inequality and segregation along racial and, to a lesser extent, gender and (dis)ability lines. Depending on their situation, learners with disabilities may be accommodated within the mainstream system, homeschooled or attend specialised schools, often far away from their homes, families and support networks. The educational experience of such learners was disrupted during the past two years due to stringent measures in response to the COVID-19 pandemic. Measures ranged from total shutdown to a shift to emergency remote teaching and learning through digital technology. This scenario brought the stark digital inequalities which characterise the South African context sharply into focus. At the same time, in some cases, digital tools provide a unique opportunity to overcome some of the challenges associated with special needs education. In this paper, I explore the narratives and experiences of learners with disabilities by conducting a qualitative content analysis of online texts such as news articles, videos, posts and relative comments. A focus on experience is consistent with current theoretical understandings of (dis)ability which seek to critique and overcome the deficit or social construction models still informing public narratives. Interpretation of the data within its social context captures the complexity and diversity of special needs education in South Africa and provides a Global South perspective.
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Date Issued: 2022

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Photo-and thermoresponsive N-salicylideneaniline derivatives: solid-state studies and structural aspects

- Hulushe, Siyabonga T, Malan, Frederick P, Hosten, Eric C, Lobb, Kevin A, Khanye, Setshaba D, Watkins, Gareth M

Authors: Hulushe, Siyabonga T , Malan, Frederick P , Hosten, Eric C , Lobb, Kevin A , Khanye, Setshaba D , Watkins, Gareth M
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/451137 , vital:75021 , xlink:href="https://pubs.rsc.org/en/content/articlehtml/2022/nj/d1nj03056f"
Description: N-Salicylideneaniline (SA) and its derivatives are known to possess chromism upon exposure to external stimuli. Herein, we present mechanochemical synthesis of a series of photo-and thermoresponsive SAderivatives and report on solid-state stabilisation of their tautomeric forms either by change in temperature or by photoirradiation. The influence of UV light on proton transfer between the enol-imine (EI) and keto-amine (KA) forms was investigated at l1 = 254 and l2 = 365 nm. Differential scanning calorimetry (DSC) measurements provided extra information on the thermodynamic relationship between the prototropic tautomers, and their exposition to liquid nitrogen, combined with variable temperature single-crystal X-ray diffraction (VT-SCXRD) and spectroscopic data, ascertained structural reasons for the intrinsic thermo-optical properties of the compounds. A series of structural determinations between 150 and 300 K further shed light on the thermomechanical behaviour exhibited by the thermoresponsive compounds. By virtue of calorimetry we were able to demonstrate proton transfer via the intramolecular ON hydrogen bond over the temperature range 193–453 K. This present work demonstrates the importance of applying complementary analytical techniques and appropriate approaches for understanding the switching behaviour between the EI and KA forms. Furthermore, the assertion that it is predominantly the planarity (j o 251) that determines thermochromaticity is questioned.
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Date Issued: 2022

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Photodegradation of ibuprofen using 5-10-15-20-tetrakis (4-bromophenyl) porphyrin conjugated to graphene quantum dots

- Magaela, N Bridged, Ndlovu, Knowledge S, Tshangana, Charmaine S, Muleia, Adoph A, Mamba, Bhekie B, Nyokong, Tebello, Managa, Muthumuni

Authors: Magaela, N Bridged , Ndlovu, Knowledge S , Tshangana, Charmaine S , Muleia, Adoph A , Mamba, Bhekie B , Nyokong, Tebello , Managa, Muthumuni
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/304819 , vital:58493 , xlink:href="https://doi.org/10.1016/j.optmat.2022.113147"
Description: Ibuprofen (IBU) is a common anti-inflammatory drug that is consumed by many individuals in the world. As such, analytical studies have detected high concentrations of the drug in many waterbodies, which poses a risk of harmful effects on the environment and public health. The hydroxyl radical technologies, a collective of techniques also known as advanced oxidation processes (AOPs), can be utilized to degrade this emerging pollutant. In this study, the photodegradation of ibuprofen using 5,10,15,20-tetrakis(4-bromophenyl) porphyrin conjugated to graphene quantum dots was investigated using a custom-built photoreactor. Three different concentrations of IBU (200, 300 and 500 μM) were utilized as initial concentrations. The pH of the IBU was varied between acidic (pH 3.0), natural (pH 5.0) and alkaline (pH 9.0) to note the effect on IBU degradation as a function of time. The Highest ФΔ was obtained for InTBrP- GDQs (ФΔ = 0.80), followed by InTBrP (ФΔ = 0.74). The photodegradation efficiency of the TBrP-GQDs and InTBrP-GQDs were determined to be 43.2 and 76.1% respectively.
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Date Issued: 2022

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Photodegradation of tetracycline by asymmetrical zinc (II) phthalocyanines conjugated to cobalt tungstate nanoparticles

- Mgidlana, Sithi, Sen, Pinar, Nyokong, Tebello

Authors: Mgidlana, Sithi , Sen, Pinar , Nyokong, Tebello
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/300233 , vital:57908 , xlink:href="https://doi.org/10.1016/j.molstruc.2022.132938"
Description: This work focused on syntheses of novel asymmetrically tetra substituted Zn phthalocyanines (ZnPc) each containing a single carboxyl group, with the other substituents bearing alkynyl (complex 1) and fluorine containing groups (complexes 2 and 3). The complexes were conjugated to cobalt tungstate nanoparticles and employed as efficient photocatalysts for degradation of tetracycline in water. ZnPc complexes and their conjugates showed good photophysical and photochemical properties behaviour with complex 1 giving higher triplet and singlet oxygen quantum yields compared to 2 and 3. Complex 1 showed higher activity towards the photodegradation of tetracycline compared to complexes 2 and 3, with higher kobs and initial rates for the former. The photocatalysis obeyed the Langmuir-Hinshelwood kinetic model.
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Date Issued: 2022

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Photodynamic activity of novel cationic porphyrins conjugated to graphene quantum dots against Staphylococcus aureus

- Magaela, N Bridged, Makola, Lekgowa C, Managa, Muthumuni, Nyokong, Tebello

Authors: Magaela, N Bridged , Makola, Lekgowa C , Managa, Muthumuni , Nyokong, Tebello
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/295797 , vital:57379 , xlink:href="https://doi.org/10.1142/S1088424622500316"
Description: Novel 5-(pyridyl)-10-15-20-tris(4-bromophenyl) porphyrin (complex 1), indium metal derivative (complex 2), and quaternized derivative (complex 3) were synthesized and conjugated to graphene quantum dots (GQDs). The conjugation of the porphyrins to GQDs was through ππ-ππ stacking. Herein, the ππ-ππ stacking approach was used to avoid covalent conjugation which might compromise the intrinsic chemical and physical properties. The photodynamic activities of the proposed nanomaterials were assessed towards Staphylococcus aureus cell obliteration. The photophysical properties of the prepared complexes were also studied prior to the application. Moreover, a decrease in fluorescence lifetimes was observed upon metalation of complex 1. As anticipated, singlet oxygen quantum yield (ΦΔ)ΦΔ) increased notably upon heavy metal (indium) insertion and upon composite formation. Antimicrobial photodynamic therapy comparative studies were done on quaternized and unquaternized indium porphyrins conjugated to GQDs. Complex 3-GQDs exhibited the highest antibacterial activities compared to other complexes, and this was attributed to the high ΦΔΦΔ which plays an imperative role in photodynamic therapy applications.
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Date Issued: 2022

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Photodynamic therapy activity of 5, 10, 15-tris (5-bromo-2-thienyl), 20 (phenylcarboxy) porphyrin conjugated to graphene quantum dot against MCF-7 breast cancer cells

- Makola, Lekgowa Collen, Nwahahra, Nnamdi, Managa, Muthumuni, Nyokong, Tebello

Authors: Makola, Lekgowa Collen , Nwahahra, Nnamdi , Managa, Muthumuni , Nyokong, Tebello
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/300244 , vital:57909 , xlink:href="https://doi.org/10.1080/00958972.2022.2087515"
Description: A novel 5,10,15-tris(5-bromo-2-thienyl),20(phenylcarboxy)porphyrin and its gallium derivative have been synthesized and fully characterized by various spectroscopic techniques and their respective photophysical and photochemical properties, such as the singlet oxygen quantum yield (ΦΔ), fluorescence quantum yield (ΦF) and triplet lifetime (τT) were determined. The complexes were conjugated to PEI_GQDs resulting is stable conjugates, owing to strong π–π stacking interaction between the PEI_GQDs and the porphyrins. PDT studies were carried out on these nanoconjugates and results obtained indicated they are suitable candidates for further in-depth PDT studies.
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Date Issued: 2022

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Photodynamic therapy characteristics of phthalocyanines in the presence of boron doped detonation nanodiamonds

- Matshitse, Refilwe, Nwaji, Njemuwa, Managa, Muthimuni, Chen, Zhi-Long, Nyokong, Tebello

Authors: Matshitse, Refilwe , Nwaji, Njemuwa , Managa, Muthimuni , Chen, Zhi-Long , Nyokong, Tebello
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/229921 , vital:49723 , xlink:href="https://doi.org/10.1016/j.pdpdt.2021.102705"
Description: The synthesis, photophysicochemical and photodynamic therapy (PDT) activities of benzothiazole substituted zinc phthalocyanine (Pc): 1 (asymmetrically substituted and composed of no charges), 2 (asymmetrically substituted and composed of three positive charges), and 3 (symmetrically substituted and composed of four positive charges), are presented. The triplet and singlet oxygen quantum yields were highest for complex 2 showing the importance of asymmetry and charge. The complexes are covalently and non-covalently linked to B doped detonation nanodiamonds (B@DNDs) to yield nanohybrids (B@DNDs-1, B@DNDs-2, B@DNDs-3). The presence of B@DNDs, asymmetry and positive charge resulted in improved PDT with the lowest cell viability being observed for B@DNDs-2 at 5%. The cell viability ranged from 5% to 7% for the nanohybrids compared to 19–26% for Pcs alone.
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Date Issued: 2022

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Phthalocyanine based fabricated exfoliated graphite photoanode for electrodegradation of 4-acetamidophenol under visible light irradiation

- Mpeta, Lekhetho S, Nyokong, Tebello

Authors: Mpeta, Lekhetho S , Nyokong, Tebello
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/295809 , vital:57380 , xlink:href="https://doi.org/10.1016/j.jphotochem.2022.114115"
Description: In this study exfoliated graphite (EG) was prepared from natural graphite flakes and incorporated with zinc phthalocyanine for fabrication of photoanode. The electron transfer capabilities of fabricated photoanode were examined by using cyclic voltammetry, electrochemical impedance spectroscopy and scanning electrochemical microscopy. Electrophotocatalytic degradation of 4-acetamidophenol in 0.1 M Na2SO4 electrolyte was performed. The photoanode with zinc phthalocyanine (EG-ZnPc) displayed better degradation compared to when only exfoliated graphite was used (EG). Furthermore, electrophotocatalytic degradation gave better performance (removal efficiency of 47.76%) than when individual electrochemical degradation and photodegradation techniques were used.
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Date Issued: 2022

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Plagiarism and the commodification of knowledge

- McKenna, Sioux

Authors: McKenna, Sioux
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/426967 , vital:72404 , xlink:href="https://doi.org/10.1007/s10734-022-00926-5"
Description: Universities have put in place various policies and punishments to manage plagiarism and it is an issue of signifcant interest. This article looks at how plagiarism is discussed in the 55 Higher Education articles between 1982 and June 2022 that make some reference to the term. Many of the articles focused on a police-catch-punish approach and imbued a strong moral charge to the issue. In contrast to such articles were those that presented citation as a complex academic practice that needs to be engaged with educationally. Our understandings of and responses to plagiarism emerge from a number of causal mechanisms but I argue that a key mechanism is the commodifcation of knowledge. Where knowledge is a product to be packaged, bought, and sold, then ownership and attribution become more important than engagement and personal meaning making. Instead of our obsession with a police-catch-punish approach to plagiarism, at a more micro-level, we should be inducting students into the many roles citations serve, and at a macro-level, we should be engaging in considerations of the purposes of a higher education and how we might better enable students to enjoy a transformative relationship to knowledge.
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Date Issued: 2022

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