List of Titles

Reaction of Perrhenate with Phthalocyanine Derivatives in the Presence of Reducing Agents and Rhenium Oxide Nanoparticles in Biomedical Applications

- Ntsimango, Songeziwe, Gandidzanwa, Sendibitiyosi, Joseph, Sinelizwi V, Hosten, Eric C, Randall, Marvin, Edkins, Adrienne L, Khene, Samson M, Mashazi, Philani N, Nyokong, Tebello, Abrahams, Abubak’r, Tshentu, Zenixole R

Authors: Ntsimango, Songeziwe , Gandidzanwa, Sendibitiyosi , Joseph, Sinelizwi V , Hosten, Eric C , Randall, Marvin , Edkins, Adrienne L , Khene, Samson M , Mashazi, Philani N , Nyokong, Tebello , Abrahams, Abubak’r , Tshentu, Zenixole R
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/300257 , vital:57910 , xlink:href="https://doi.org/10.1002/open.202200037"
Description: A novel alternative route to access rhenium(V)−phthalocyanine complexes through direct metalation of metal-free phthalocyanines (H2Pcs) with a rhenium(VII) salt in the presence of various two-electron reducing agents is presented. Direct ion metalation of tetraamino- or tetranitrophthalocyanine with perrhenate (ReO4−) in the presence of triphenylphosphine led to oxidative decomposition of the H2Pcs, giving their respective phthalonitriles. Conversely, treatment of H2Pcs with ReO4− employing sodium metabisulfite yielded the desired ReVO−Pc complex. Finally, reaction of H2Pcs with ReO4− and NaBH4 as reducing agent led to the formation of rhenium oxide (RexOy) nanoparticles (NPs). The NP synthesis was optimised, and the RexOy NPs were capped with folic acid (FA) conjugated with tetraaminophthalocyanine (TAPc) to enhance their cancer cell targeting ability. The cytotoxicity profile of the resultant RexOy−TAPc−FA NPs was assessed and found to be greater than 80 % viability in four cell lines, namely, MDA−MB-231, HCC7, HCC1806 and HEK293T. Non-cytotoxic concentrations were determined and employed in cancer cell localization studies. The particle size effect on localization of NPs was also investigated using confocal fluorescence and transmission electron microscopy. The smaller NPs (≈10 nm) were found to exhibit stronger fluorescence properties than the ≈50 nm NPs and exhibited better cell localization ability than the ≈50 nm NPs.
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Date Issued: 2022

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Refining youth sexualities empowerment programmes: The development of the Masizixhobise Toolkit based on a critical sexual and reproductive citizenship framework

- Macleod, Catriona I, Moore, Sarah-Ann

Authors: Macleod, Catriona I , Moore, Sarah-Ann
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , book chapter
Identifier: http://hdl.handle.net/10962/434158 , vital:73035 , ISBN 9781003139782 , https://www.taylorfrancis.com/chapters/edit/10.4324/9781003139782-15/refining-youth-sexualities-empowerment-programmes-catriona-ida-macleod-sarah-moore
Description: Youth sexualities programmes frequently focus on empowering young people in relation to sexual decision-making and interactions. Within these programmes, however, empowerment is mostly equated with the individualised concepts of self-efficacy and agency to the exclusion of interpersonal and social (i.e. collective) components. Resultantly, the social justice aspects of empowerment may be overlooked. Noting this, some researchers have argued for the adoption of a broader, integrative conceptualisation of empowerment. Macleod’s and Vincent’s critical sexual and reproductive citizenship (CSRC) framework provides such a conceptualisation. This framework draws from feminist re-workings of the principles of citizenship and applies these to understandings of CSRC. Based on this framework, key issues for consideration in programmes are: sexual and reproductive citizenship as status and practice; situated agency; differentiated universalism; the interweaving of the private and public; and the politics of recognition, redistribution and reparation. This chapter discusses the development of a programme refinement toolkit based on a CSRC framework, named the Masizixhobise Toolkit; how the elements outlined above were operationalised into questions; an illustrative example; and the partnership formed with a youth empowerment non-governmental organisation in developing the toolkit.
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Date Issued: 2022

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Reflections from early-career researchers on the past, present and future of doctoral education

- Mason, Shannon, Lévesque, Maude, Meki-Kombe, Charity, Abel, Sophie, Balaban, Corina, Chiappa, Roxana, Grund, Martin, Joubert, Biandri, Kuchumova, Gulfiya, Mantai, Lilia, Main, Joyce, Motshoane, Puleng, Qi, Jing, Steyn, Ronel, Zheng, Gaoming

Authors: Mason, Shannon , Lévesque, Maude , Meki-Kombe, Charity , Abel, Sophie , Balaban, Corina , Chiappa, Roxana , Grund, Martin , Joubert, Biandri , Kuchumova, Gulfiya , Mantai, Lilia , Main, Joyce , Motshoane, Puleng , Qi, Jing , Steyn, Ronel , Zheng, Gaoming
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , book chapter
Identifier: http://hdl.handle.net/10962/434543 , vital:73075 , ISBN 9781800080218 , https://library.oapen.org/bitstream/handle/20.500.12657/58197/1/9781800080188.pdf#page=264
Description: Early-career researchers (ECRs) played a unique and explicit role in the development of the Hannover Recommendations 2019. We, the ECRs, were the recipients of competitive travel scholarships generously funded by Volkswagen Stiftung, whose support brought us together from across the globe. Attendance at the culminating conference in Germany presented an opportunity for some that would have otherwise been inaccessible without that support. Our role was to work alongside established scholars to design and develop a set of recommendations to provide a foundation for the future of doctoral education internationally. We each participated in different capacities, with some members of the group joining preliminary pre-conference online meetings and contributing to group discussions at the workshop in the days prior to the conference, which also involved the drafting of written reports. Others joined later in the process, participating in the discussions that were a central part of the conference proceedings. During the events we also had informal opportunities to discuss issues related to various aspects of doctoral education. Although we participated in varying degrees and contexts, we each contributed to discussions on the current status and future directions of doctoral education globally.
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Date Issued: 2022

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Regioselectivity, chemical bonding and physical nature of the interaction between imidazole and XAHs (X= H, F, Cl, Br, CH3, and A= S, Se, Te)

- Isamura, Bienfait K, Lobb, Kevin A, Muya, Jules T

Authors: Isamura, Bienfait K , Lobb, Kevin A , Muya, Jules T
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/453183 , vital:75229 , xlink:href="https://doi.org/10.1080/00268976.2022.2026511"
Description: Theambidentreactivityofsmall-sizedXAHs(X=H,F,Cl,Br,CH3,andA=S,Se,Te)moleculestowardsthe imidazole molecule (IMZ) has been investigated using wave function (MP2) and Density Func-tional Theory (B3LYP, B3LYP-D3). Molecular electrostatic potentials (MEPs) and frontier molecularorbitals of monomers are computed to rationalise the regioselectivity of IMZ towards XAHs. Thechemical bonding of each complex is described in the framework of the quantum theory of atomsin molecules (QTAIM) and natural bond orbital (NBO) paradigms. The symmetry-adapted pertur-bation theory (SAPT) is employed to assess the physical nature of the interactions. Our findingssuggest that XAHs mainly bind to IMZ through H-bonding and chalcogen-bonding interactionsof weak to moderate strength, with binding energies ranging from−3.1 to−17.6 kcal/mol at theMP2/aug-cc-pVDZ(-PP) level. Topological QTAIM descriptors reveal all H-bonds between IMZ andXAHs to be purely noncovalent contacts, while chalcogen bonds of halogenated XAHs (X=F, Cl, Br) show a partial covalent character. SAPT2 calculations indicate that both H-bonded and chalcogen-bonded complexes are mainly stabilised by electrostatic interactions. Insights drawn from this studyare expected to constitute the bedrock for further investigations about noncovalent interactionbetween middle to big-sized chalcogen-containing molecules and imidazole derivatives.
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Date Issued: 2022

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Reproductive health systems analyses and the reparative reproductive justice approach: a case study of unsafe abortion in Lesotho

- Macleod, Catriona I, Reynolds, John H

Authors: Macleod, Catriona I , Reynolds, John H
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/441288 , vital:73874 , xlink:href="https://doi.org/10.1080/17441692.2021.1887317"
Description: Health systems analyses are touted as mechanisms through which health policy and planning may be implemented. An example is the WHO health systems approach that connects people (needs, rights, perspectives) with services and technologies (equitable access, quality of care, mix of interventions) and with policies and institutional capacities (laws, regulations, human/physical resources, management and financing). The approach is comprehensive and multi-faceted, which is a strength. We argue, however, that health systems analyses should be supplemented with a focus on reproductive justice. Using the WHO health systems approach as an exemplar, we show how the reparative reproductive justice approach outlined by the first author and colleagues assists with outlining comprehensive remedies to the inequities identified in the systems analysis. We argue for attention to remedies at individual and collective, material and symbolic levels. We illustrate our argument using unsafe abortion, legal abortion services and post-abortion care in Lesotho as a case study. We outline the policies, services and people components of abortion in Lesotho using the WHO systems model, followed by a reparative justice analysis of remedies.
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Date Issued: 2022

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Review of Importance of Weather and Environmental Variables in Agent-Based Arbovirus Models

- Pascoe, Luba, Clemen, Thomas, Bradshaw, Karen L, Nyambo, Devotha G

Authors: Pascoe, Luba , Clemen, Thomas , Bradshaw, Karen L , Nyambo, Devotha G
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/440300 , vital:73764 , xlink:href="https://doi.org/10.3390/ijerph192315578"
Description: The study sought to review the works of literature on agent-based modeling and the influence of climatic and environmental factors on disease outbreak, transmission, and surveillance. Thus, drawing the influence of environmental variables such as vegetation index, households, mosquito habitats, breeding sites, and climatic variables including precipitation or rainfall, temperature, wind speed, and relative humidity on dengue disease modeling using the agent-based model in an African context and globally was the aim of the study. A search strategy was developed and used to search for relevant articles from four databases, namely, PubMed, Scopus, Research4Life, and Google Scholar. Inclusion criteria were developed, and 20 articles met the criteria and have been included in the review. From the reviewed works of literature, the study observed that climatic and environmental factors may influence the arbovirus disease outbreak, transmission, and surveillance. Thus, there is a call for further research on the area. To benefit from arbovirus modeling, it is crucial to consider the influence of climatic and environmental factors, especially in Africa, where there are limited studies exploring this phenomenon.
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Date Issued: 2022

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Season and environment modulate aquatic invertebrates’ responses to trout and indigenous fishes in three South African mountain streams

- Bellingan, Terence A, Hugo, Sanet, Villet, Martin H, Weyl, Olaf L F

Authors: Bellingan, Terence A , Hugo, Sanet , Villet, Martin H , Weyl, Olaf L F
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/441487 , vital:73893 , https://doi.org/10.3389/fenvs.2022.1004939
Description: Introduced organisms are seen as one of the greatest threats to resource sustainability worldwide, and aquatic macroinvertebrates are regarded as good indicators of the health of water resources. To explore these two perspectives, the responses of macroinvertebrate faunas to native and introduced fishes in three headwater tributaries of the Keiskamma River system, South Africa, were examined by comparing potential indicator communities in reaches considered to be fishless, reaches invaded by introduced salmonid species, and reaches containing native fishes. Patterns in the macroinvertebrate faunal assemblage data were driven strongly by season and flow rate, and less strongly by the presence of insectivorous fishes and biotope availability, a finding in parallel with several similar studies from the region. This affirms that aquatic macroinvertebrate faunas are responsive indicators of both environmental and biotic factors and leaves room for further studies to resolve the effects of non-native fish in the Keiskamma River system and other similar systems from South Africa.
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Date Issued: 2022

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Shrub Detection in High-Resolution Imagery: A Comparative Study of Two Deep Learning Approaches

- James, Katherine M F, Bradshaw, Karen L

Authors: James, Katherine M F , Bradshaw, Karen L
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , book
Identifier: http://hdl.handle.net/10962/440326 , vital:73766 , ISBN 9783030955021 , https://doi.org/10.1007/978-3-030-95502-1_41
Description: A common task in high-resolution remotely-sensed aerial imagery is the detection of particular target plant species for various ecological and agricultural applications. Although traditionally object-based image analysis approaches have been the most popular method for this task, deep learning approaches such as image patch-based convolutional neural networks (CNNs) have been seen to outperform these older approaches. To a lesser extent, fully convolutional networks (FCNs) that allow for semantic segmentation of images, have also begun to be used in the broader literature. This study investigates patch-based CNNs and FCN-based segmentation for shrub detection, targeting a particular invasive shrub genus. The results show that while a patch-based CNN demonstrates strong performance on ideal image patches, the FCN outperforms this approach on real-world proposed image patches with a 52% higher object-level precision and comparable recall. This indicates that FCN-based segmentation approaches are a promising alternative to patch-based approaches, with the added advantage of not requiring any hand-tuning of a patch proposal algorithm.
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Date Issued: 2022

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Situating the diversity of Southern African environmental education scholarship within a global conversation at a critical juncture on Earth

- Olvitt, Lausanne L

Authors: Olvitt, Lausanne L
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/389869 , vital:68491 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/247386"
Description: ¬The collection of papers in Volume 38 in many ways mirrors the diversity of research methodologies and teaching approaches in the contemporary eld of Environmental and Sustainability Education. ¬ e seven papers remind us that, whilst environmental educators and researchers are largely in agreement over the nature and causes of the social-ecological problems that we face in sub-Saharan Africa, there is less certainty around what types of educational approaches and pedagogies are adequate to help resolve them. ¬ e papers in this volume either o er pedagogical innovations that may strengthen teaching and learning for sustainable futures, or they provide insights into the social, cultural and economic contexts in which such teaching and learning occurs.
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Date Issued: 2022

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Small but strong: Socioeconomic and ecological resilience of a small European fishing community affected by a submarine volcanic eruption

- De la Cruz-Modino, Raquel, Piñeiro-Corbeira, Cristina, Gutiérrez-Barroso, Josué, González-Cruz, Carla, Barreiro, Rodolfo, Batista-Medina, José A, Pascual-Fernández, José, González, José A, Santana-Talavera, Agustín, Aswani, Shankar

Authors: De la Cruz-Modino, Raquel , Piñeiro-Corbeira, Cristina , Gutiérrez-Barroso, Josué , González-Cruz, Carla , Barreiro, Rodolfo , Batista-Medina, José A , Pascual-Fernández, José , González, José A , Santana-Talavera, Agustín , Aswani, Shankar
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/391397 , vital:68648 , xlink:href="https://doi.org/10.1016/j.ocecoaman.2022.106124"
Description: Small-scale coastal fishing communities are facing many new challenges, such as rapid ecological changes created by anthropogenic and natural events like earthquakes or volcanic eruptions. This paper explores how a coastal population has responded to such an event and highlights the diverse coping strategies used to tackle it. This research was conducted on the island of El Hierro (Spain), where a submarine volcanic eruption occurred in 2011, affecting a multiple-use Marine Protected Area (MPA) and the nearby fishing community of La Restinga. Our study illustrates how the local population coped with this situation by combining multiple monetary and non-monetary activities (e.g., informal exchanges) as well as the role of institutions in increasing local resilience by supporting fishers' demands and allowing their participation in the decision-making process in the immediate wake of a catastrophic event. Local families also exploited various natural resources in and near the MPA, thus ensuring access to crucial marine resources and continued recreational/cultural services. The results suggest that collective action played a key role in the recovery process after the eruption, creating some advantages for different local groups despite the hazardous nature of the event.
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Date Issued: 2022

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Sn (IV) porphyrin-biotin decorated nitrogen doped graphene quantum dots nanohybrids for photodynamic therapy

- Magaela, N Bridged, Matshitse, Refilwe, Balaji, Babu, Managa, Muthumuni, Prinsloo, Earl, Nyokong, Tebello

Authors: Magaela, N Bridged , Matshitse, Refilwe , Balaji, Babu , Managa, Muthumuni , Prinsloo, Earl , Nyokong, Tebello
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/230018 , vital:49733 , xlink:href="https://doi.org/10.1016/j.poly.2021.115624"
Description: Photodynamic therapy (PDT) is a minimally invasive therapeutic procedure for cancer treatment. This study focuses on the synthesis, photophysicochemical properties, and PDT activity of Sn (IV) porphyrin (2), when linked to biotin decorated nitrogen doped graphene quantum dots (B-NGQDs). The porphyrin complex 2 was conjugated through an ester bond to B-NGQDs to form 2-B-NGQDs. Singlet oxygen quantum yield increased for 2 when linked to B-NGQDs to form 2-B-NQGDs. The dark toxicity and photodynamic therapy studies were conducted for 2, NGQDs and their conjugates using MCF-7 breast cancer cells. The cell viability for dark toxicity of all the compounds was above 90%, and 2-B-NGQDs showed high PDT activity at a concentration of 40 µg/mL with cell viability of 22%.
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Date Issued: 2022

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Social, ethical and cultural responsibility as core values for doctoral researchers in the 21st century

- Chiappa, Roxana, Cantini, Danielle, Karakasoglu, Yasemin, Manathunga, Catherine, Peters, Christian, Scholz, Beate, Yarar, Betul

Authors: Chiappa, Roxana , Cantini, Danielle , Karakasoglu, Yasemin , Manathunga, Catherine , Peters, Christian , Scholz, Beate , Yarar, Betul
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , book chapter
Identifier: http://hdl.handle.net/10962/434515 , vital:73072 , ISBN 9781800080218 , 10.14324/111.9781800080188
Description: With the dramatic events of a global pandemic, the beginning of the twenty-first century’s third decade has underlined that the world is facing universal challenges. The worldwide crisis scenario that COVID-19 has produced makes us realise that science and research do not function and operate in an independent sphere hidden within the proverbial ivory tower, but, on the contrary, are closely linked to the social, cultural and political systems they reside in. This creates opportunities and great tensions and, while exploring those, Chapter 9 connects to and builds on most of the dimensions described in the previous sections of the book. We refer primarily to Hannover Recommendations 1 and 7: 1. Establish a global joint value system for doctoral education based on an ecology of knowledges which recognises and seeks to overcome existing inequalities in the access to doctoral education and the provision of knowledge. 7. The pivotal goal of doctoral education must be and remain the development of original, responsible, and ethical thinkers, and the generation of new and original ideas and knowledge.
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Date Issued: 2022

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Social-ecological change: insights from the Southern African Program on Ecosystem Change and Society

- Biggs, Reinette, Clements, Hayley S, Cumming, Graeme S, Cundill, Georgina, de Vos, Alta, Hamann, Maike, Luvuno, Linda, Roux, Dirk J, Selomane, Odirlwe, Blanchard, Ryan, Cockburn, Jessica J, Dziba, Luthando E, Esler, Karen J, Fabricius, Christo, Henriksson, Rebecka, Kotschy, Karen, Lindborg, Regina, Masterson, Vanessa A, Nel, Jeanne L, O'Farrell, Patrick, Palmer, Carolyn G, Pereira, Laura, Pollard, Sharon, Preiser, Rika, Scholes, Robert J, Shackleton, Charlie M, Shackleton, Sheona E, Sitas, Nadia, Slingsby, Jasper A, Spierenburg, Maria, Tengö, Maria, Reyers, Belinda

Authors: Biggs, Reinette , Clements, Hayley S , Cumming, Graeme S , Cundill, Georgina , de Vos, Alta , Hamann, Maike , Luvuno, Linda , Roux, Dirk J , Selomane, Odirlwe , Blanchard, Ryan , Cockburn, Jessica J , Dziba, Luthando E , Esler, Karen J , Fabricius, Christo , Henriksson, Rebecka , Kotschy, Karen , Lindborg, Regina , Masterson, Vanessa A , Nel, Jeanne L , O'Farrell, Patrick , Palmer, Carolyn G , Pereira, Laura , Pollard, Sharon , Preiser, Rika , Scholes, Robert J , Shackleton, Charlie M , Shackleton, Sheona E , Sitas, Nadia , Slingsby, Jasper A , Spierenburg, Maria , Tengö, Maria , Reyers, Belinda
Date: 2022
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/399817 , vital:69561 , xlink:href="https://doi.org/10.1080/26395916.2022.2097478"
Description: Social-ecological systems (SES) research has emerged as an important area of sustainability science, informing and supporting pressing issues of transformation towards more sustainable, just and equitable futures. To date, much SES research has been done in or from the Global North, where the challenges and contexts for supporting sustainability transformations are substantially different from the Global South. This paper synthesises emerging insights on SES dynamics that can inform actions and advance research to support sustainability transformations specifically in the southern African context. The paper draws on work linked to members of the Southern African Program on Ecosystem Change and Society (SAPECS), a leading SES research network in the region, synthesizing key insights with respect to the five core themes of SAPECS: (i) transdisciplinary and engaged research, (ii) ecosystem services and human well-being, (iii) governance institutions and management practices, (iv) spatial relationships and cross-scale connections, and (v) regime shifts, traps and transformations. For each theme, we focus on insights that are particularly novel, interesting or important in the southern African context, and reflect on key research gaps and emerging frontiers for SES research in the region going forward. Such place-based insights are important for understanding the variation in SES dynamics around the world, and are crucial for informing a context-sensitive global agenda to foster sustainability transformations at local to global scales.
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Date Issued: 2022

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