Synthesis, structure and in vitro anti-trypanosomal activity of non-toxic Arylpyrrole-Based Chalcone derivatives:
- Authors: Zulu, Ayanda I , Oderinlo, Ogunyemi O , Kruger, Cuan , Isaacs, Michelle , Hoppe, Heinrich C , Smith, Vincent J , Veale, Clinton G L , Khanye, Setshaba D
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/179017 , vital:40096 , https://doi.org/10.3390/molecules25071668
- Description: With an intention of identifying chalcone derivatives exhibiting anti-protozoal activity, a cohort of relatively unexplored arylpyrrole-based chalcone derivatives were synthesized in moderate to good yields. The resultant compounds were evaluated in vitro for their potential activity against a cultured Trypanosoma brucei brucei 427 strain. Several compounds displayed mostly modest in vitro anti-trypanosomal activity with compounds 10e and 10h emerging as active candidates with IC50 values of 4.09 and 5.11 µM, respectively. More importantly, a concomitant assessment of their activity against a human cervix adenocarcinoma (HeLa) cell line revealed that these compounds are non-toxic.
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Synthetic, characterization and cytotoxic studies of ruthenium complexes with Schiff bases encompassing biologically relevant moieties:
- Authors: Maikoo, Sanam , Dingle, Laura M K , Chakraborty, Abir , Xulu, Bheki , Edkins, Adrienne L , Booysen, Irvin N
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/165429 , vital:41243 , https://doi.org/10.1016/j.poly.2020.114569
- Description: This research study describes the formation and characterization of novel paramagnetic ruthenium complexes, cis-Cl, trans-P-[RuIIICl2(carboim)(PPh3)2] with bidentate chelating carbohydrazide Schiff bases (carboim = bpc for 1, ttc for 2 and tpc for 3). These metal complexes were synthesized by the equimolar coordination reactions of trans-[RuCl2(PPh3)2] with N-[1,3-benzothiazole-2-ylmethylidene]pyridine-2-carbohydrazide (Hbpc), N-((uracil-5-yl)methylene)thiophene-2-carbohydrazide (Httc) and N-[(uracil-5-yl)methylidene]pyridine-2-carbohydrazide (Htpc), respectively. Physicochemical techniques including nuclear magnetic resonance-, electron-spin resonance- and infrared spectroscopy, UV–Vis spectrophotometry, voltammetry as well as molar conductivity measurements provided definitive determinations of the respective ruthenium compounds’ structures.
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Temperature tolerance and humidity requirements of select entomopathogenic fungal isolates for future use in citrus IPM programmes
- Authors: Acheampong, M A , Coombes, Candice A , Moore, Sean D , Hill, Martin P
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/419399 , vital:71641 , xlink:href="https://doi.org/10.1016/j.jip.2020.107436"
- Description: Several isolates of Beauveria bassiana (Balsamo-Crivelli) Vuillemin (Hypocreales: Cordycipitacae) and Metarhizium anisopliae (Metchnikoff) Sorokin (Hypocreales: Clavicipitacae) have been investigated as possible microbial control agents of key citrus pests in South Africa. Although laboratory results have been promising, field trials against foliar pests have shown limited success. These findings highlighted the need to investigate other biological attributes of these fungal isolates besides virulence in order to select candidates that may be better suited for the foliar environment. Thus, this study investigated the influence of temperature on the in vitro growth of seven indigenous local isolates and the humidity requirements necessary to promote successful infection, in comparison with two commercial isolates (B. bassiana PPRI 5339 and M. anisopliae ICIPE 69). All the fungal isolates grew across a range of temperatures (8–34 °C) and optimally between 26 and 28 °C. Similarly, fungal infection of Thaumatotibia leucotreta Meyrick (Lepidoptera: Tortricidae) fifth instars occurred across a range of humidity levels (12%, 43%, 75%, 98%) regardless of fungal concentration, although external sporulation was restricted to treatments exposed to 98% relative humidity. It was concluded that neither temperature nor humidity, when considered alone, is likely to significantly influence the efficacy of any of the isolates in the field, given that they are active within temperature and humidity ranges experienced in South African citrus orchards.
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The alternative theory of state-minded protest texts in the music of democratic Nigeria:
- Authors: Osiebe, Garhe
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/160423 , vital:40444 , DOI: 10.1080/21681392.2020.1810085
- Description: This paper centres on an alternative discourse of popular music culture in re-democratized Nigeria. Whereas much work has been done on state-minded protest music in Nigeria, studies have been reticent in appreciating the works of Fela's son, Femi; particularly within a framework of re-democratized Nigeria's equivalent of Fela's works which constituted a major alternative voice through military-ruled Nigeria. The paper is an attempt to make up this lacuna along the lines of Chris Atton’s 2006 alternative media theory. The analysis of the alternative media theory is complemented by an analysis of the texts of selected state-minded protest works from two crossover popular musicians – Blackface and Mr Raw – of re-democratized Nigeria, both of whose state-minded protest works have hitherto been unexplored by the academe.
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The conundrums of counselling women in violent intimate partner relationships in South Africa: implications for practice
- Authors: Fleischack, Anne , Macleod, Catriona I , Böhmke, Werner
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444117 , vital:74191 , xlink:href="https://doi.org/10.1007/s10447-019-09384-8"
- Description: Little research focuses on how counsellors experience counselling encounters concerning intimate partner violence. This study reports on narrative research conducted with eight South African non-governmental organisation counsellors. Participants spoke of creating productive and caring counselling dynamics, and providing non-directive counselling. However, they also indicated providing moral guidance, particularly in cases where pregnancy or children were involved. Success was viewed rather narrowly as the women leaving the relationship, setting up ‘all-or-nothing’ outcomes. Such ‘success’ led to counsellor happiness, whilst failure in this regard led to counsellors experiencing anger and burn-out. We conclude that the conundrums evident in these data are grounded in patriarchal systems, limiting the efficacy of counselling based on a bondage and deliverance narrative. Implications for practice and training are also outlined.
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The crystal structure of 2-oxo-2H-chromen-4-yl acetate, C11H8O4
- Authors: Hulushe, Siya T , Manyeruke, Meloddy H , Hosten, Eric C , Kaye, Perry , Watkins, Gareth M
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/194048 , vital:45418 , xlink:href="https://doi.org/10.1515/ncrs-2019-0698"
- Description: C11H8O4, monoclinic, P21/c (no. 14), a = 4.5947(2) Å, b = 10.5414(3) Å, c = 19.1611(7) Å, β = 94.084(2)°, V = 925.70(6) Å3, Z = 4, Rgt(F) = 0.0376, wRref(F 2) = 0.1109,T = 200(2) K.CCDC no.: 1906383
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The cultural history of Augustan Rome: texts, monuments, and topography ed. by Matthew P. Loar et al
- Authors: Pandey, Nandini B
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149658 , vital:38872 , https://muse.jhu.edu/article/755534
- Description: This edited collection, the product of a 2014 conference at Notre Dame's Rome Global Gateway, asks "what the texts in, on, and about the city of Rome tell us about how the ancients thought about, interacted with, and responded to the city during the transition from Republic to Empire" (1). Given the enormity of the topic, this slender volume makes no claim to comprehensive treatment. What it offers, instead, is a high-quality sampling with suggestions for future research (8-9) that will reward anyone interested in responsions between Augustan writing and building.
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The degree, extent and value of air temperature amelioration by urban green spaces in Bulawayo, Zimbabwe:
- Authors: Ngulani, T , Shackleton, Charlie M
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/176061 , vital:42656 , https://doi.org/10.1080/03736245.2019.1685405
- Description: Urban greenery provide a variety of goods and services to city dwellers. A core one is amelioration of the urban heat island effect. However, the many estimates from temperate regions cannot be extrapolated to the tropics, where more empirical studies are required to guide urban planning and optimization of green infrastructure design and distribution. This study reports on the temperature differentials in fortnightly readings, in winter and summer, between 12 urban green spaces and the surrounding built-up urban matrix at increasing distances from each green space. Additionally, the value of energy costs saved for air conditioning by urban greenery was calculated.
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The Effects of Alkaline Pretreatment on Agricultural Biomasses (Corn Cob and Sweet Sorghum Bagasse) and Their Hydrolysis by a Termite-Derived Enzyme Cocktail:
- Authors: Mafa, Mpho S , Malgas, Samkelo , Bhattacharya, Abhishek , Rashamuse, Konanani , Pletschke, Brett I
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/160273 , vital:40430 , https://doi.org/10.3390/agronomy10081211
- Description: Sweet sorghum bagasse (SSB) and corncob (CC) have been identified as promising feedstocks for the production of second-generation biofuels and other value-added chemicals. In this study, lime (Ca(OH)2) and NaOH pretreatment efficacy for decreasing recalcitrance from SSB and CC was investigated, and subsequently, the pretreated biomass was subjected to the hydrolytic action of an in-house formulated holocellulolytic enzyme cocktail (HEC-H). Compositional analysis revealed that SSB contained 29.34% lignin, 17.75% cellulose and 16.28% hemicellulose, while CC consisted of 22.51% lignin, 23.58% cellulose and 33.34% hemicellulose. Alkaline pretreatment was more effective in pretreating CC biomass compared to the SSB biomass.
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The effects of asymmetry in combination with reduced graphene oxide nanosheets on hydrazine electrocatalytic detection on cobalt phthalocyanines
- Authors: Mpeta, Lekhetho S , Sen, Pinar , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186023 , vital:44456 , xlink:href="https://doi.org/10.1002/elan.202060094"
- Description: New symmetric {tetrakis [4-(4-(5-chloro-1Hbenzo[d]imidazol-2-yl) phenoxy phthalocyaninato] Co (II) (CoTPc)} and low symmetry {tris tert butyl phenoxy mono [4-(4-(5-chloro-1H-benzo[d]imidazol-2-yl) phenoxy phthalocyaninato]} Co (II) (CoMPc) were successfully synthesised and combined with reduced graphene oxide nanosheets (rGONS) for electrocatalytic detection of hydrazine. Prior to electrocatalysis, the probes were characterised using cyclic voltammetry and electrochemical impedance spectroscopy. Chronoamperometry was used to determine catalytic rate constant and the limit of detection (LOD). CoMPc-rGONS gave catalytic rate constant and LOD of 1.37×106 M 1 s 1 and 0.82 μM respectively, rendering it a more suitable probe for hydrazine, due to low symmetry.
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The establishment and rapid spread of Sagittaria Platyphylla in South Africa:
- Authors: Ndlovu, Mpilonhle S , Coetzee, Julie A , Nxumalo, Menzi M , Lalla, Reshnee , Shabalala, Ntombifuthi , Martin, Grant D
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149788 , vital:38884 , https://doi.org/10.3390/w12051472
- Description: Sagittaria platyphylla Engelm. (Alismataceae) is a freshwater aquatic macrophyte that has become an important invasive weed in freshwater systems in South Africa, New Zealand, Australia, and recently China. In South Africa, due to its rapid increase in distribution and ineffective control options, it is recognised as one of the country’s worst invasive aquatic alien plants. In this paper, we investigate the spread of the plant since its first detection in 2008, and the management strategies currently carried out against it. Despite early detection and rapid response programmes, which included chemical and mechanical control measures, the plant was able to spread both within and between sites, increasing from just one site in 2008 to 72 by 2019. Once introduced into a lotic system, the plant was able to spread rapidly, in some cases up to 120 km within 6 years, with an average of 10 km per year. The plant was successfully extirpated at some sites, however, due to the failure of chemical and mechanical control, biological control is currently being considered as a potential control option.
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The feasibility of prolonged exposure therapy for PTSD in low-and middle-income countries: a review
- Authors: Booysen, Duane D , Kagee, Ashraf
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148505 , vital:38745 , DOI: 10.1080/20008198.2020.1753941
- Description: There is a need in the global south to evaluate and implement empirically supported psychological interventions to ameliorate symptoms of posttraumatic stress disorder (PTSD). Empirically supported treatments (ESTs) have increasingly been developed and implemented, yet the majority people in the global south do not have access to these treatments for mental disorders such as PTSD. Prolonged exposure therapy has accrued substantial empirical evidence to show it as an effective treatment for PTSD. Research on the effectiveness and acceptability of prolonged exposure in a low- and middle-income countries (LMICs) are sparse. This brief report presents a review of prolonged exposure (PE) therapy and its feasibility as a trauma therapy for PTSD in LMICs. First, we present a brief overview of PE as a first-line treatment for PTSD. Second, using South Africa as a case example, we present a brief overview of traumatic stress in South Africa and how mental healthcare has developed since the abolishment of apartheid in 1994. Lastly, we discuss the challenges pertaining to the dissemination and implementation of PE in LMICs and propose future perspectives regarding the implementation of ESTs such as PE in LMICs.
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The genetic legacy of fragmentation and overexploitation in the threatened medicinal African pepper-bark tree, Warburgia salutaris:
- Authors: Senkoro, Annae M , Talhinhas, Pedro , Simões, Fernanda , Batista-Santos, Paula , Shackleton, Charlie M , Voeks, Robert A , Marques, Isabel , Ribeiro-Barros, Ana I
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/176395 , vital:42690 , https://doi.org/10.1016/j.ecoser.2020.101201
- Description: The pepper-bark tree (Warburgia salutaris) is one of the most highly valued medicinal plant species worldwide. Native to southern Africa, this species has been extensively harvested for the bark, which is widely used in traditional health practices. Illegal harvesting coupled with habitat degradation has contributed to fragmentation of populations and a severe decline in its distribution. Even though the species is included in the IUCN Red List as Endangered, genetic data that would help conservation efforts and future re-introductions are absent. We therefore developed new molecular markers to understand patterns of genetic diversity, structure, and gene flow of W. salutaris in one of its most important areas of occurrence (Mozambique).
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The impact of formulation variables on the optimization of pilot scale clobetasol 17-propionate creams
- Authors: Fauzee, Ayesha F B , Walker, Roderick B
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183275 , vital:43937 , xlink:href="https://doi.org/10.1080/23311916.2020.1804713"
- Description: The impact of formulation variables on the optimization of pilot scale clobetasol 17-propionate (CP) cream formulations was investigated using a Central Composite Design of Experiments. Thirty batches of cream were manufactured and the formulation variables assessed were % v/v propylene glycol, % w/w Gelot® 64, cetostearyl alcohol and glyceryl monostearate content. The responses monitored included viscosity, spreadability, pH, CP content, extrudability, electrical conductivity, and % CP released at 72 hours. The responses were compared to those of a reference product, Dermovate® cream. ANOVA analysis revealed that viscosity, spreadability, and % CP released at 72 hours were significant formulation responses (p more than 0.05). Cetostearyl alcohol had the greatest impact on quality of pilot scale products. An increase in cetostearyl alcohol resulted in an increase in viscosity, a decrease in spreadability, and a decrease in % CP released at 72 hours. The optimized pilot scale CP formulation contained 46% v/v propylene glycol, 8.6% w/w cetostearyl alcohol, 10.5% w/w glyceryl monostearate, and 3.8% w/w Gelot® 64. The resultant viscosity, spreadability, pH, CP content, extrudability, electrical conductivity, and % CP released were 44633cP, 24.91cm2, 101.23 %, 76.98 g/cm2, 198.23 µS/cm, and 50.23%. The addition of cetostearyl alcohol and Gelot® 64 is critical for establishing a soft formulation that leads to the formation of a mixed crystal bilayer network of high viscosity. The formation of a separate crystalline lipophilic network usually occurs in semi-solid formulations that contain high concentrations of emulsifier, leading to an increase in shear stress and greater physicochemical stability of the formulation. The use of experimental design approaches to formulation development activities, permit evaluation of multiple factors simultaneously, reducing the time and costs associated with product development activities, whilst identifying a composition design space and ensuring stable and effective dosage forms are produced.
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The impact of illustrated side effect information on understanding and sustained retention of antiretroviral side effect knowledge:
- Authors: Scheihing, Konstantin W , Tanner, Jane L , Weaver, Matthew J T , Schöniger, Matthias
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156389 , vital:39985 , https://doi.org/10.1016/j.jup.2020.101043
- Description: About 7.5 million South Africans access gratuitous drinking water via communal taps provided by municipalities under a free basic water policy. Supplying running water for free to low-income communities is essential but can result in water wastage due to a potential indifference of non-paying end-consumers. The consequence is a loss of municipal water and financial resources. We outline a new strategy that rewards low-income communities for reducing water wastage. The incentive strategy promotes water conservation and community development and decreases recurring water-related public expenses. The concept is funded by a percentage of municipal cost savings yielded from the respective water conservation.
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The In Silico Prediction of hotspot residues that contribute to the structural stability of subunit interfaces of a Picornavirus Capsid:
- Authors: Upfold, Nicole , Ross, Caroline J , Tastan Bishop, Özlem , Knox, Caroline M
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149970 , vital:38919 , https://doi.org/10.3390/v12040387
- Description: The assembly of picornavirus capsids proceeds through the stepwise oligomerization of capsid protein subunits and depends on interactions between critical residues known as hotspots. Few studies have described the identification of hotspot residues at the protein subunit interfaces of the picornavirus capsid, some of which could represent novel drug targets. Using a combination of accessible web servers for hotspot prediction, we performed a comprehensive bioinformatic analysis of the hotspot residues at the intraprotomer, interprotomer and interpentamer interfaces of the Theiler’s murine encephalomyelitis virus (TMEV) capsid.
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The in vitro antiplasmodial and antiproliferative activity of new ferrocene-based α-aminocresols targeting hemozoin inhibition and DNA interaction:
- Authors: Mbaba, Mziyanda , Dingle, Laura M K , Swart, Tarryn , Cash, Devon , Laming, Dustin , de la Mare, Jo-Anne , Taylor, Dale , Hoppe, Heinrich C , Biot, Christophe , Edkins, Adrienne L , Khanye, Setshaba D
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149347 , vital:38827 , https://0-doi.org.wam.seals.ac.za/10.1002/cbic.202000132
- Description: Compounds incorporating ferrocene in a aminocresol scaffold showed antiplasmodial and anticancer activity. SAR studies revealed that an OH group and rotatable C–NH bond are vital for biological activity, with spectrophotometric techniques and docking simulations suggesting a dual mode of action involving hemozoin inhibition and DNA interaction. Targeting multiple pathways could delay the development of clinical resistance.
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The influence of citrus orchard age on the ecology of entomopathogenic fungi and nematodes
- Authors: Albertyn ,Sonnica , Moore, Sean D , Marsberg, Tamryn , Coombes, Candice A , Hill, Martin P
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/417545 , vital:71462 , xlink:href="https://hdl.handle.net/10520/ejc-cristal-v10-n1-a7"
- Description: A three-year survey of the ecology of entomopathogenic nematodes (EPN) and entomopathogenic fungi (EPF) was undertaken on soils from citrus orchards of different ages to determine the influence of orchard age on the ecology of entomopathogenic fungi and nematodes. The influence of mulch and irrigation method on the occurrence of EPN and EPF was also determined. Most of the isolates recovered (n = 810) were Beauveria sp. (87.88% of all isolates), followed by Metarhizium sp. (11.87% of all isolates). Only 0.24% of soil samples collected during this study tested positive for EPN. All EPN isolates recovered were Heterorhabditis bacteriophora. No significant differences in EPF occurrence were recorded between orchards under drip and micro-sprinkler irrigation. EPF occurrence was significantly lower (P = 0.016) in orchards covered by mulch (31.85% ± 2.07% occurrence) than in orchards with no covering (38.57% ± 1.57% occurrence). EPF occurrence of 40.33 ± 2.13% was highest in non-bearing orchards, followed by mature orchards (nine years or older) (36.76 ± 2.05% of samples) with the lowest EPF occurrence of 25.30 ± 2.02% reported in juvenile orchards (four to eight years old). Juvenile orchards sustain significantly less EPF than mature and non-bearing orchards because of the combined negative impact of less favourable environmental conditions (lower shade density) and fungicide applications.
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The invasive grass genus Nassella in South Africa: A synthesis
- Authors: Mapaura Anthony , Canavan, Kim N , Richardson, David M , Clark, Vincent R , Steenhuisen, Sandy-Lynn
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/424842 , vital:72188 , xlink:href="https://doi.org/10.1016/j.sajb.2020.08.031"
- Description: Three species of Nassella have naturalized in South Africa. Nassella trichotoma and N. tenuissima are declared weeds under category 1b of the National Environmental Management: Biodiversity Act (NEM:BA) and occur mainly in the montane grasslands of the Western and Eastern Cape provinces. Nassella neesiana is not listed in NEM:BA but is naturalized in the Eastern Cape, Western Cape and Free State provinces. Research conducted in the 1970s and 1980s led to vigorous government-funded awareness and control campaigns which ended in 2000. No research on Nassella distribution or control has been undertaken since then. Despite this hiatus, Nassella remains a dangerous genus in southern Africa, given the serious impacts of these species in similar social-ecological systems in Australia and New Zealand. This paper presents a synthesis of available information about Nassella invasions in South Africa and identifies research gaps. It specifically addresses these questions: What identification issues exist? What is the current spatial distribution of Nassella? What is the autecology of the genus? What are the social-ecological impacts of Nassella? What control measures are currently applied and what are their strengths and limitations? What do we know about Nassella distribution and its response to climate change? This paper highlights many knowledge gaps about Nassella, such as the species’ current distribution range, field identification and detection difficulties, and the uncoordinated control efforts that require urgent research to inform an effective management response.
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The Legacy Effects of Colonial and Apartheid Imprints on Urban Greening in South Africa: Spaces, Species, and Suitability
- Authors: Shackleton, Charlie M , Gwedla, Nanamhla
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/176296 , vital:42682 , https://doi.org/10.3389/fevo.2020.579813
- Description: Colonialism is a significant legacy across most aspects of urban form, the nature and distribution of public green spaces, and tree species composition in many cities of the Global South. However, the legacy effects of colonialism on urban green infrastructure and the uses thereof have only recently come under scrutiny. Here we collate information from South Africa on urban greening and interpret it through a colonial and apartheid legacy lens in relation to the distribution and types of urban nature found and their resonance with contemporary needs as an African country.
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