Being Brave: Writing Environmental Education Research
- Authors: Lotz-Sisitka, Heila , Burt, Jane C
- Date: 2002
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184734 , vital:44267 , xlink:href="https://eric.ed.gov/?id=EJ654591"
- Description: The heroine came back from her very important quest and sat down to write a thesis . . . While mythical journeys do not always end this way, the stories have to be told. The work of telling the story in the hero’s journey is often left untold. This paper explores some of the headwork that goes into textwork (Van Manen, 1995) in environmental education research. We argue that writing is an integral part of the research process, and should not be viewed as an “add on” or a silent, untold part of the adventure. We reflect on some of the institutional and epistemological issues associated with writing social science (in our case environmental education) research texts. Writing research is never an easy enterprise, it is bound by history and tradition, convention, institutional habit, and regulation. It is also constrained by the uncertainty of the process of writing itself, by problems of power relations in research, and the difficulty of writing to represent experience rigorously and authentically while recognizing that all writing is a constructed symbolic representation of experience. The paper reflexively reviews our attempts at “being brave” in the construction of our research texts.
- Full Text:
- Date Issued: 2002
The role and value of savanna non-timber forest products to rural households in the Kat River Valley, South Africa
- Authors: Shackleton, Charlie M , Shackleton, Sheona E , Ntshudu, M , Ntzebeza, J
- Date: 2002
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182820 , vital:43882 , xlink:href="https://www.cabdirect.org/cabdirect/abstract/20023145773"
- Description: The majority of South Africans reside in rural areas characterized by limited infrastructure and employment opportunities. Many, therefore, make extensive use of non-timber-forest products (NTFPs) as part of their daily livelihoods. However, until recently, there were relatively few quantitative studies on resources used, amounts and frequencies. This is especially so for the savanna biome in South Africa, even though it is the largest biome. This paper presents data from a quantitative study of resource use and value in three villages situated in the savannas of the poorest province of South Africa. The results demonstrated widespread use of a wide variety of NTFPs. There were no households that did not make use of at least one NTFP from the surrounding woodlands. The five contributing most to the total gross value per household were fuelwood, wild herbs, wild fruits, bushmeat and honey beer. The mean gross annual direct-use value at the three villages ranged from US$211 to US$324 per household, averaged across user and non-user households. The direct-use value to user households was approximately double this. The net value differed between specific NTFPs because of differential labour input. The net value represented between 39 and 86% of the gross value, with a mean of 63%. However, the use of opportunity costs of labour in such areas requires examination.
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- Date Issued: 2002
Trade in reed-based craft products in rural villages in the Eastern Cape, South Africa
- Authors: Pereira, Taryn , Shackleton, Charlie M , Shackleton, Sheona E
- Date: 2006
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181290 , vital:43716 , xlink:href="https://doi.org/10.1080/03768350600927235"
- Description: Selling traditional craft products made from fibrous plants is an important source of income for economically vulnerable rural women. In the Eastern Cape Province of South Africa, Cyperus textilis and Juncus kraussii have been used for centuries to make products of functional and cultural importance, such as sleeping mats and baskets. In the former Transkei village clusters of Mpozolo and Ntubeni, female crafters harvest the raw material and make and sell the products in their communities and in nearby towns. Interviews with 40 of them revealed what the trade contributes to their livelihoods and what enhances or limits their success. The findings show that crafting contributes vital income to vulnerable households, on average 26 ± 4 per cent of annual household cash income, over 40 per cent for the poorest households and 5–15 per cent for wealthier households. Lack of access to non-traditional markets was identified as the main constraint on the trade.
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- Date Issued: 2006
Children navigating rural poverty: Rural children's use of wild resources to counteract food insecurity in the Eastern Cape, South Africa
- Authors: McGarry, Dylan K , Shackleton, Charlie M
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181191 , vital:43706 , xlink:href="https://doi.org/10.1080/10796120802677594"
- Description: This paper analyzes the role of natural resources in the lives of rural children experiencing heightened vulnerability to poverty and the impact of HIV/AIDS, a subject that previously has been unexplored. The authors highlight wild-food use by rural children as a regular activity that supplements their domestic diets. Over the course of 18 months in the Eastern Cape of South Africa, the authors used a broad quantitative and qualitative methodology to explore the food acquisition and consumption patterns for 850 children. They found that the quality of children's domestic diets was, on average, 60% lower than the Food and Agricultural Organization (FAO) guidelines. This occurred in a population where 62% of the children surveyed were supplementing their diets with wild foods; and 30% with over half their diet supplemented in this way. Significantly, dietary diversity increased by 13% when wild food supplementation occurred. Another result was the commercialization of wild foods (observed among 47% of the children), wherein significantly more vulnerable children sold these foods. Considering the heightened nutritional and energy needs of children, combined with the impact of poverty and HIV/AIDS on household food access, wild foods represent the last freely attainable food sources available to them.
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- Date Issued: 2009
Ethics-oriented learning in environmental education workplaces: An activity theory approach
- Authors: Olvitt, Lausanne L
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/370961 , vital:66398 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122874"
- Description: In the context of increasing national and global environmental challenges and their implications for the working world, new ethics and practices are being introduced into workplaces that take better account of socio-ecological relations. Little is understood, however, about the nature of ethics-oriented workplace learning. Drawing on Cultural Historical Activity Theory (CHAT), which enables historically and contextually situated relational perspectives to emerge, this paper explores contradictions in the activity systems of two young environmental education learner-practitioners struggling to engage with the ethical dimensions of their professional work and the professional development course they are studying. The study focuses in particular on the environmental values and ethics component of their course – a year-long Learnership in Environmental Education, Training and Development Practices (EETDP). The paper reflects how tensions and contradictions within and between the interacting activity systems of the workplace, the course, and its regulating qualifications authority influence the teaching and learning of the environmental ethics component of the course. Ethics-oriented teaching and learning processes are found to be strongly influenced by the ‘rules’ and ‘mediating tools’ of these interacting systems, but these are often at odds with the ethical perspectives, socio-cultural context and skills of the ‘subject’ and ‘community’. These systemic contradictions can be more fully understood when their cultural and historical origins are made explicit. The analytical process has led to a more nuanced understanding of ethics-oriented teaching and learning in a workplace-based course, and has revealed several areas needing more careful research (particularly the area of environmental discourses) and the explicit and implicit language of ethics.
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- Date Issued: 2010
The Makana Regional Centre of expertise: Experiments in social learning
- Authors: Lotz-Sisitka, Heila , O'Donoghue, Rob , Wilmot, P Dianne
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182634 , vital:43849 , xlink:href="https://doi.org/10.1177/097340820900400114"
- Description: This article deliberates the possibilities for Regional Centres of Expertise (RCEs) to become ‘experiments’ in social learning. The purpose of the article is to advance the broader research agenda of RCEs through reflection on the empirical research agenda of one RCE, Makana RCE in South Africa. As such it opens questions on how we might see RCE’s as morphogenic social learning processes (i.e., processes of social change). It provides an oversight of the key issues, educational foci and developing areas of engagement in the Makana RCE. These provide an overview of the ‘starting points’ for social learning in the Makana RCE. A model of social learning is also provided which seeks to engage the ecocultural nature of sustainability practices in the Makana RCE.
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- Date Issued: 2010
The determinants of household savings in South Africa
- Authors: Simleit, C , Keeotn, Gavin , Botha, Ferdi
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396153 , vital:69154 , xlink:href="https://hdl.handle.net/10520/EJC21526"
- Description: In South Africa, substantial government dissaving as well as poor household savings performance has caused a decline in aggregate savings. Whilst government dissaving has been successfully reversed, household savings continue to fall. Low domestic savings have required South Africa to attract large, volatile portfolio capital inflows to fund a structural current account deficit. Repeated reversals of such inflows have constrained domestic growth and hence an understanding of the factors that have caused this decline in savings is essential in order to formulate policies supportive of sustained higher rates of economic growth. Within the context of the existing literature, this article examines the various determinants of household savings using a vector error-correction model (VECM). The results suggest that interest rates, a wealth effect and upturns in the business cycle all contribute to explaining the decline in household savings. The presence of a partial offset between household savings and government savings also has important implications for the effectiveness of using the fiscal position of the South African government to boost savings.
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- Date Issued: 2011
The art of dying
- Authors: Jones, Ward E
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/275722 , vital:55073 , xlink:href="https://doi.org/10.1080/05568641.2012.743217"
- Description: In this paper, I explore what Jean Améry calls the ‘aesthetic view of death’. I address the following three questions. To what extent, and how, do we take an aesthetic view of death? Why do we take an aesthetic view of death? Third, for those whose deaths are impending and have some choice over how they die—most prominently the elderly and the terminally ill—what would it mean for them to take an aesthetic view of their own impending deaths, and, in particular, what would it mean for them to act in the light of such a view?
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- Date Issued: 2012
Family functioning and life satisfaction and happiness in South African households
- Authors: Botha, Ferdi , Booysen, Frikkie
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396048 , vital:69146 , xlink:href="https://doi.org/10.1007/s11205-013-0485-6"
- Description: Families form an integral part of society and in fostering individual well-being. Despite the acknowledged importance of family, the association between family functioning and individual well-being outcomes have remained unexplored in the current body of knowledge. This paper explores the association between family functioning and reported levels of life satisfaction and happiness in South Africa. The paper employs the Family Attachment and Changeability Index (FACI8) to measure family functioning, using data from the 2011 South African Social Attitudes Survey. Four measures of family functioning are utilised, namely the aggregate FACI8 scale, the attachment and changeability sub-scales, and family functioning type. Improvements in the level of family functioning as well as in the levels of attachment and changeability are positively associated with life satisfaction and happiness. In addition, individuals living in midrange or balanced family functioning types are more satisfied with life and happier compared to persons living in extremely or moderately dysfunctional families. The findings highlight the importance of supportive intra-family dynamics in fostering greater individual well-being. This in turn places emphasis on the investigation of likely correlates of family functioning and impact evaluations of family-focused social work interventions’ impact on family functioning as areas for future research.
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- Date Issued: 2014
Happiness, socioeconomic status, and family functioning in South African households
- Authors: Botha, Ferdie , Booysen, Frikkie
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396075 , vital:69148 , xlink:href="https://doi.org/10.1007/s11205-013-0485-6"
- Description: This paper examines how SES relates to individual happiness, while also controlling for family functioning; the latter measured by the Family Attachment and Changeability Index 8 (FACI8). An individual-, household-, and subjective SES index are developed via multiple correspondence analyses (MCA). Using data from the 2012 South African Social Attitudes Survey (SASAS), the paper employs structural equation modelling (SEM) to explore the relationship between happiness, SES, and family functioning. Multiple-group SEM (MGSEM) is employed to examine the association between happiness and family functioning across quartiles of the three SES indices. The results reveal that higher SES is significantly related to greater happiness, with the role of household- and subjective SES being stronger than individual SES. Furthermore, improved levels of family changeability are positively associated with happiness, whereas there is no relationship between happiness and family attachment. Overall, levels of family changeability and individual happiness are likely to benefit from improvements in socioeconomic status.
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- Date Issued: 2014
Baculovirus-based strategies for the management of insect pests: a focus on development and application in South Africa
- Authors: Knox, Caroline M , Moore, Sean D , Luke, Garry , Hill, Martin P
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/416829 , vital:71389 , xlink:href="https://doi.org/10.1080/09583157.2014.949222"
- Description: There is growing concern among governments, scientists, agricultural practitioners and the general public regarding the negative implications of widespread synthetic chemical pesticide application for the control of crop pests. As a result, baculovirus biopesticides are gaining popularity as components of integrated pest management (IPM) programmes in many countries despite several disadvantages related to slow speed of kill, limited host range and complex large scale production. In South Africa, baculoviruses are incorporated into IPM programmes for the control of crop pests in the field, and recent bioprospecting has led to the characterisation of several novel isolates with the potential to be formulated as commercial products. This contribution will provide an overview of the use of baculoviruses against insect pests in South Africa, as well as research and development efforts aimed at broadening their application as biocontrol agents. Challenges faced by researchers in developmental projects as well as potential users of baculoviruses as biopesticides in the field are also discussed.
- Full Text:
- Date Issued: 2015
Facilitators for and barriers to the implementation of National Tuberculosis Management Guidelines
- Authors: Dlwati, Lucretia V , Mavundla, Thandisizwe R , Mbengo, Fungai
- Date: 2017
- Subjects: TB management , National Tuberculosis Management Guidelines , Normalization Process Model
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/11260/5569 , vital:44607 , https://doi.org/10.25159/2520-5293/2862
- Description: The South African government developed the National Tuberculosis Management Guidelines (NTBMGs) to provide guidance to professional healthcare workers on the management of people with TB and also those co-infected with HIV. However, little is known about primary healthcare (PHC) nurses perceptions of the implementation of the NTBMGs, despite their critical role in TB management. The purpose of this study was to explore PHC nurses perception of the implementation of the NTBMGs in order to identify factors influencing the implementation of the NTBMGs and to make recommendations to improve the implementation of the NTBMGs. The study was conducted in the Eastern Cape, South Africa. The Normalization Process Model (NPM) was used as a theoretical framework to understand the factors influencing the implementation of the NTBMGs. A qualitative, explorative, descriptive and contextual research design was utilised. Data were collected using individual semi-structured interviews on a purposive sample of PHC nurses working in rural clinics. Data were analysed following a descriptive method of Tesch. The study revealed several facilitators for and barriers to the implementation of the NTBMGs based on the NPM. The facilitators included the PHC nurses satisfaction with the Directly Observed Treatment, Short Course (DOTS) strategy in rendering health services to TB patients, the PHC nurses perception of TB meetings as an appropriate platform for problem-solving, of the NTBMGs to be consistent with TB management, and of job satisfaction in relation to patient improvement. The barriers included poverty, inadequate training, shortage of staff, and a lack of material resources, a proper infection control policy, and space. There is a need for the provision of adequate human, material and infrastructural resources in order to eliminate the barriers to the implementation of the NTBMGs.
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- Date Issued: 2017
Cropland abandonment in South African smallholder communal lands: Land cover change (1950–2010) and farmer perceptions of contributing factors
- Authors: Blair, Dale , Shackleton, Charlie M , Mograbi, Penelope J
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180297 , vital:43351 , xlink:href="https://doi.org/10.3390/land7040121"
- Description: Despite agricultural land abandonment threatening the food security and the livelihoods of smallholder farmers, it is pervasive globally and in developing countries. Yet land abandonment is an understudied aspect of land use change in social–ecological systems. Here we provide more information on this phenomenon by exploring cropland abandonment during 1950–2010 in four former South African ‘homelands’—part of the ‘Apartheid’ era racially-based land allocation programs—characterized by rural, smallholder farmers. Cropland abandonment 1950–2010 was widespread in all surveyed sites (KwaZulu: 0.08% year−1, Transkei: 0.13% year−1, Lebowa: 0.23% year−1, Venda: 0.28% year−1), with rates peaking between 1970 and 1990, with concomitant increases (up to 0.16% year−1) of woody vegetation cover at the expense of grassland cover. Active and past farmers attributed cropland abandonment to a lack of draught power, rainfall variability and droughts, and a more modernized youth disinclined to living a marginal agrarian lifestyle. We discuss the potential social and ecological implications of abandoned croplands at the local and regional scales, as the deagrarianization trend is unlikely to abate considering the failure of current South African national agricultural incentives.
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- Date Issued: 2018
A spatio-temporal, landscape perspective on Acacia dealbata invasions and broader land use and cover changes in the northern Eastern Cape, South Africa
- Authors: Gouws, Aidan J , Prof.Shackleton, Charlie M
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/179670 , vital:43156 , xlink:href="https://doi.org/10.1007/s10661-019-7204-y"
- Description: Biological invasions and human land use both have the potential to drastically alter the patterns and processes of landscapes, driving habitat fragmentation and altering natural disturbance regimes. The proliferation of an invasive species depends on composition and configuration of the landscape, as well as the invasiveness of the species. To effectively manage a highly invasive species, such as Acacia dealbata, it is crucial to understand the historical progression of the invasion within the landscape. This study sought to examine the landscape dynamics of biological invasions by tracking the historical spread of A. dealbata and broader land use/land cover (LULC) changes at different spatiotemporal scales in the northern Eastern Cape. A timeseries of aerial photographs were systematically classified according to designated A. dealbata and LULC categories in ArcGIS to track the changes in the extent and rate of spread of A. dealbata. Markedly dynamic, multi-directional, and spatio-temporally variable LULC transitions were observed across the northern Eastern Cape over the last six decades. A. dealbata frequently retained a high proportion of cover over time, and despite the loss of cover to other LULC classes, a net increase in A. dealbata cover occurred as it spread at an overall annual rate of 0.11–0.21%, occupying approximately 8–18% of land cover across all sampled sites by 2013.
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- Date Issued: 2019
Methodological Survey of Simplified TD-DFT Methods for Fast and Accurate Interpretation of UV−Vis−NIR Spectra of Phthalocyanines
- Authors: Martynov, Alexander G , Mack, John , May, Aviwe K , Nyokong, Tebello , Gorbunova, Yulia G , Tsivadze, Aslan Yu
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186915 , vital:44547 , xlink:href="https://doi.org/10.1021/acsomega.8b03500"
- Description: A methodological survey of density functional theory (DFT) methods for the prediction of UV−visible (vis)−near-infrared (NIR) spectra of phthalocyanines is reported. Four methods, namely, full time-dependent (TD)-DFT and its Tamm−Dancoff approximation (TDA), together with their simplified modifications (sTD-DFT and sTDA, respectively), were tested by using the examples of unsubstituted and alkoxy-substituted metal-free ligands and zinc complexes. The theoretical results were compared with experimental data derived from UV−visible absorption and magnetic circular dichroism spectroscopy. Seven popular exchange-correlation functionals (BP86, B3LYP, TPSSh, M06, CAM-B3LYP, LC-BLYP, and ωB97X) were tested within these four approaches starting at a relatively modest level using 6-31G(d) basis sets and gas-phase BP86/def2-SVP optimized geometries. A gradual augmentation of the computational levels was used to identify the influence of starting geometry, solvation effects, and basis sets on the results of TD-DFT and sTD-DFT calculations. It was found that although these factors do influence the predicted energies of the vertical excitations, they do not affect the trends predicted in the spectral properties across series of structurally related substituted free bases and metallophthalocyanines. The best accuracy for the gas-phase vertical excitations was observed in the lower-energy Q-band region for calculations that made use of range-separated hybrids for both full and simplified TD-DFT approaches. The CAMB3LYP functional provided particularly accurate results in the context of the sTD-DFT approach. The description of the higherenergy B-band region is considerably less accurate, and this demonstrates the need for further advances in the accuracy of theoretical calculations. Together with a general increase in accuracy, the application of simplified TD-DFT methods affords a 2−3 orders of magnitude speedup of the calculations in comparison to the full TD-DFT approach. It is anticipated that this approach will be widely used on desktop computers during the interpretation of UV−vis−NIR spectra of phthalocyanines and related macrocycles in the years ahead.
- Full Text:
- Date Issued: 2019
Research for the people, by the people: The political practice of cognitive justice and transformative learning in environmental social movements
- Authors: Burt, Jane C
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/392177 , vital:68728 , xlink:href="https://doi.org/10.3390/su11205611"
- Description: This paper describes how Changing Practice courses, developed by environmental activists in South Africa and based on social learning practice, have seeded cognitive justice action. For the educator-activists who facilitated these courses, it became apparent that we needed a bold emancipatory pedagogy which included cognitive justice issues. This enabled us and the activist-researcher participants to understand the extent to which local, indigenous, and spiritual knowledge had been excluded from water governance. The paper investigates how participants in the ‘Water and Tradition’ change project, established by the Vaal Environmental Justice Alliance (VEJA, engaged with cognitive justice, to demonstrate how African spiritual practice offers a re-visioning of the natural world. Finally, using the tools of critical realist theory, the paper reviews how VEJA bring about transformative social action through their participation in the Changing Practice course.
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- Date Issued: 2019
Stability indicating HPLC-ECD method for the analysis of clarithromycin in pharmaceutical dosage forms: Method scaling versus re-validation.
- Authors: Makoni, Pedzisai A , Chikukwa, Mellisa , Khamanga, Sandile M , Walker, Roderick B
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183387 , vital:43984 , xlink:href="https://doi.org/10.3390/scipharm87040031"
- Description: An isocratic high-performance liquid chromatographic method using electrochemical detection (HPLC-ECD) for the quantitation of clarithromycin (CLA) was developed using Response Surface Methodology (RSM) based on a Central Composite Design (CCD). The method was validated using International Conference on Harmonization (ICH) guidelines with an analytical run time of 20 min. Method re-validation following a change in analytical column was successful in reducing the analytical run time to 13 min, decreasing solvent consumption thus facilitating environmental and financial sustainability. The applicability of using the United States Pharmacopeia (USP) method scaling approach in place of method re-validation using a column with a different L–designation to the original analytical column, was investigated. The scaled method met all USP system suitability requirements for resolution, tailing factor and % relative standard deviation (RSD). The re-validated and scaled method was successfully used to resolve CLA from manufacturing excipients in commercially available dosage forms. Although USP method scaling is only permitted for columns within the same L-designation, these data suggest that it may also be applicable to columns of different designation.
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- Date Issued: 2019
A career in photophysicochemical and electrochemical properties of phthalocyanine: A Linstead Career Award paper
- Authors: Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186045 , vital:44458 , xlink:href="https://doi.org/10.1142/S1088424620300037"
- Description: This manuscript highlights the author’s contributions to phthalocyanine chemistry, especially the applications based on their electrochemistry and photophysicochemistry. In particular, the use of phthalocyanines as electrocatalysts and photocatalysts is presented. For photocatalysis, photodynamic antimicrobial chemotherapy and pollution control using green technologies are highlighted. For electrocatalysis the phthalocyanines are employed for the detection of pollutants and environmentally important molecules. Phthalocyanines are combined with nanomaterials for improved photocatalysis and electrocatalysis.
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- Date Issued: 2020
A novel dimeric exoglucanase (GH5_38): Biochemical and Structural Characterisation towards its Application in Alkyl Cellobioside Synthesis
- Authors: Mafa, Mpho S , Dirr, Heinrich , Malgas, Samkelo , Krause, Rui W M , Pletschke, Brett I
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/193976 , vital:45412 , xlink:href="https://doi.org/10.3390/molecules25030746"
- Description: An exoglucanase (Exg-D) from the glycoside hydrolase family 5 subfamily 38 (GH5_38) was heterologously expressed and structurally and biochemically characterised at a molecular level for its application in alkyl glycoside synthesis. The purified Exg-D existed in both dimeric and monomeric forms in solution, which showed highest activity on mixed-linked β-glucan (88.0 and 86.7 U/mg protein, respectively) and lichenin (24.5 and 23.7 U/mg protein, respectively). They displayed a broad optimum pH range from 5.5 to 7 and a temperature optimum from 40 to 60 °C. Kinetic studies demonstrated that Exg-D had a higher affinity towards β-glucan, with a Km of 7.9 mg/mL and a kcat of 117.2 s−1, compared to lichenin which had a Km of 21.5 mg/mL and a kcat of 70.0 s−1. The circular dichroism profile of Exg-D showed that its secondary structure consisted of 11% α-helices, 36% β-strands and 53% coils. Exg-D performed transglycosylation using p-nitrophenyl cellobioside as a glycosyl donor and several primary alcohols as acceptors to produce methyl-, ethyl- and propyl-cellobiosides. These products were identified and quantified via thin-layer chromatography (TLC) and liquid chromatography–mass spectrometry (LC-MS). We concluded that Exg-D is a novel and promising oligomeric glycoside hydrolase for the one-step synthesis of alkyl glycosides with more than one monosaccharide unit.
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- Date Issued: 2020
A relational approach to landscape stewardship: Towards a new perspective for multi-actor collaboration
- Authors: Cockburn, Jessica J , Rosenberg, Eureta , Copteros, Athina , Cornelius, Susanna F , Libala, Notiswa , Metcalfe, Liz , van der Waal, Benjamin
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/370098 , vital:66297 , xlink:href="https://doi.org/10.3390/land9070224"
- Description: Landscape stewardship is increasingly understood within the framing of complex social-ecological systems. To consider the implications of this, we focus on one of the key characteristics of complex social-ecological systems: they are relationally constituted, meaning that system characteristics emerge out of dynamic relations between system components. We focus on multi-actor collaboration as a key form of relationality in landscapes, seeking a more textured understanding of the social relations between landscape actors. We draw on a set of ‘gardening tools’ to analyse the boundary-crossing work of multi-actor collaboration. These tools comprise three key concepts: relational expertise, common knowledge, and relational agency. We apply the tools to two cases of landscape stewardship in South Africa: the Langkloof Region and the Tsitsa River catchment. These landscapes are characterised by economically, socio-culturally, and politically diverse groups of actors. Our analysis reveals that history and context strongly influence relational processes, that boundary-crossing work is indeed difficult, and that doing boundary-crossing work in smaller pockets within a landscape is helpful. The tools also helped to identify three key social-relational practices which lend a new perspective on boundary-crossing work: 1. belonging while differing, 2. growing together by interacting regularly and building common knowledge, and 3. learning and adapting together with humility and empathy.
- Full Text:
- Date Issued: 2020