Interactive efficacies of Elephantorrhiza elephantina and Pentanisia prunelloides extracts and isolated compounds against gastrointestinal bacteria
- Mpofu, Smart J, Olivier, D K, Krause, Rui W M, Ndinteh, Derek T, Van Vuuren, S
- Authors: Mpofu, Smart J , Olivier, D K , Krause, Rui W M , Ndinteh, Derek T , Van Vuuren, S
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124122 , vital:35552 , https://doi.org/10.1016/j.sajb.2014.07.002
- Description: Elephantorrhiza elephantina (Burch.) Skeels (Fabaceae) and Pentanisia prunelloides (Klotzsch ex Eckl. & Zeyh.) Walp. (Rubiaceae) are two medicinal plants used extensively in southern Africa to treat various ailments. Often, decoctions and infusions from these two plants are used in combination specifically for stomach ailments. The antimicrobial activities of the methanol and aqueous extracts of the rhizomes of the two plants, as well as the two active ingredients from the plants [(−)-epicatechin and palmitic acid] have been determined apart and in combination against Enterococcus faecalis (ATCC 29212), Escherichia coli (ATCC 8739) and Bacillus cereus (ATCC 11778). The minimum inhibitory concentration (MIC) values for the aqueous (0.50–16.00 mg/mL) and methanol (0.20–16.00 mg/mL) extracts independently demonstrated varied efficacies depending on the pathogen of study. When the two plants were combined in 1:1 ratios, synergistic to additive interactions (ΣFIC values 0.19–1.00) were noted. Efficacy for the two major compounds ranged between 0.13–0.63 mg/mL and mainly synergistic interactions were noted against E. faecalis and E. coli. The predominantly synergistic interactions noted between E. elephantina and P. prunelloides and major compounds, when tested in various ratios against these pathogens, provide some validation as to the traditional use of these two plants to treat bacterial gastrointestinal infections.
- Full Text:
- Date Issued: 2014
- Authors: Mpofu, Smart J , Olivier, D K , Krause, Rui W M , Ndinteh, Derek T , Van Vuuren, S
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124122 , vital:35552 , https://doi.org/10.1016/j.sajb.2014.07.002
- Description: Elephantorrhiza elephantina (Burch.) Skeels (Fabaceae) and Pentanisia prunelloides (Klotzsch ex Eckl. & Zeyh.) Walp. (Rubiaceae) are two medicinal plants used extensively in southern Africa to treat various ailments. Often, decoctions and infusions from these two plants are used in combination specifically for stomach ailments. The antimicrobial activities of the methanol and aqueous extracts of the rhizomes of the two plants, as well as the two active ingredients from the plants [(−)-epicatechin and palmitic acid] have been determined apart and in combination against Enterococcus faecalis (ATCC 29212), Escherichia coli (ATCC 8739) and Bacillus cereus (ATCC 11778). The minimum inhibitory concentration (MIC) values for the aqueous (0.50–16.00 mg/mL) and methanol (0.20–16.00 mg/mL) extracts independently demonstrated varied efficacies depending on the pathogen of study. When the two plants were combined in 1:1 ratios, synergistic to additive interactions (ΣFIC values 0.19–1.00) were noted. Efficacy for the two major compounds ranged between 0.13–0.63 mg/mL and mainly synergistic interactions were noted against E. faecalis and E. coli. The predominantly synergistic interactions noted between E. elephantina and P. prunelloides and major compounds, when tested in various ratios against these pathogens, provide some validation as to the traditional use of these two plants to treat bacterial gastrointestinal infections.
- Full Text:
- Date Issued: 2014
Invasive alien species as drivers in socio-ecological systems: Local adaptations towards use of Lantana in Southern India
- Kannan, Ramesh, Shackleton, Charlie M, Shaanker, Ramanan U
- Authors: Kannan, Ramesh , Shackleton, Charlie M , Shaanker, Ramanan U
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180932 , vital:43671 , xlink:href="https://doi.org/10.1007/s10668-013-9500-y"
- Description: Lantana camara. L (hereafter Lantana) was first introduced by the British into India in 1807 as an ornamental plant. Since then the species has spread across the length and breadth of the country. Attempts to control Lantana in India have not been successful. In this study, we analysed the use of Lantana by local communities in southern India and identified the possible causes and consequences of its use through the use of a household survey of the socio-economic profile of the user and nonuser households and an analysis of the ecological history of the communities. Communities have been using Lantana for over 25–30 years and apparently such use was not prompted by external agencies. The characteristics of user and nonuser households were similar, except that Lantana users were more literate and had a greater number of occupations per household than nonusers. Per capita income was similar between user and nonuser groups. For nonuser groups, their main income sources were from trading (44 %), wage labour (32 %) and forest resources (23 %). In contrast, the Lantana user groups substituted their loss of income from forest resources (7 %) by income from Lantana (46 %). The ecological history revealed that Lantana was adopted as a resource at a time when it was increasing in the landscape and traditional bamboo resources were in decline because of overuse by commercial enterprises and mast flowering. This change in ecological resource availability prompted a major shift in livelihoods for some in the area.
- Full Text:
- Date Issued: 2014
- Authors: Kannan, Ramesh , Shackleton, Charlie M , Shaanker, Ramanan U
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180932 , vital:43671 , xlink:href="https://doi.org/10.1007/s10668-013-9500-y"
- Description: Lantana camara. L (hereafter Lantana) was first introduced by the British into India in 1807 as an ornamental plant. Since then the species has spread across the length and breadth of the country. Attempts to control Lantana in India have not been successful. In this study, we analysed the use of Lantana by local communities in southern India and identified the possible causes and consequences of its use through the use of a household survey of the socio-economic profile of the user and nonuser households and an analysis of the ecological history of the communities. Communities have been using Lantana for over 25–30 years and apparently such use was not prompted by external agencies. The characteristics of user and nonuser households were similar, except that Lantana users were more literate and had a greater number of occupations per household than nonusers. Per capita income was similar between user and nonuser groups. For nonuser groups, their main income sources were from trading (44 %), wage labour (32 %) and forest resources (23 %). In contrast, the Lantana user groups substituted their loss of income from forest resources (7 %) by income from Lantana (46 %). The ecological history revealed that Lantana was adopted as a resource at a time when it was increasing in the landscape and traditional bamboo resources were in decline because of overuse by commercial enterprises and mast flowering. This change in ecological resource availability prompted a major shift in livelihoods for some in the area.
- Full Text:
- Date Issued: 2014
Investigating coral reef ethnobiology in the western Solomon Islands for enhancing livelihood resilience:
- Authors: Aswani, Shankar
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/145425 , vital:38437 , DOI: 10.15286/jps.123.3.237-276
- Description: Coral reefs are of great socio-economic and cultural importance for many coastal communities across the tropics, yet little is known about people's local classifications and their social and ecological relationships with these habitats. In the case of island peoples, coral reefs are more than just resource exploitation areas; they are also géomorphologie features that allow or bar people from navigating, markers that define property rights of the seascape in relation to other coastal and terrestrial habitats, and cultural and historical features that embody tribal identity and ideology. Building upon over two decades of research, this paper uses published and unpublished data to describe people's ecological and socio-economic relationships with coral reefs in two extensive lagoon ecosystems in the Western Solomon Islands.
- Full Text:
- Date Issued: 2014
- Authors: Aswani, Shankar
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/145425 , vital:38437 , DOI: 10.15286/jps.123.3.237-276
- Description: Coral reefs are of great socio-economic and cultural importance for many coastal communities across the tropics, yet little is known about people's local classifications and their social and ecological relationships with these habitats. In the case of island peoples, coral reefs are more than just resource exploitation areas; they are also géomorphologie features that allow or bar people from navigating, markers that define property rights of the seascape in relation to other coastal and terrestrial habitats, and cultural and historical features that embody tribal identity and ideology. Building upon over two decades of research, this paper uses published and unpublished data to describe people's ecological and socio-economic relationships with coral reefs in two extensive lagoon ecosystems in the Western Solomon Islands.
- Full Text:
- Date Issued: 2014
Investigating the chaperone properties of a novel heat shock protein, Hsp70. c, from Trypanosoma brucei
- Burger, Adélle, Ludewig, Michael H, Boshoff, Aileen
- Authors: Burger, Adélle , Ludewig, Michael H , Boshoff, Aileen
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431155 , vital:72749 , xlink:href="https://doi.org/10.1155/2014/172582"
- Description: The neglected tropical disease, African Trypanosomiasis, is fatal and has a crippling impact on economic development. Heat shock protein 70 (Hsp70) is an important molecular chaperone that is expressed in response to stress and Hsp40 acts as its co-chaperone. These proteins play a wide range of roles in the cell and they are required to assist the parasite as it moves from a cold blooded insect vector to a warm blooded mammalian host. A novel cytosolic Hsp70, from Trypanosoma brucei, TbHsp70.c, contains an acidic substrate binding domain and lacks the C-terminal EEVD motif.The ability of a cytosolic Hsp40 from Trypanosoma brucei J protein 2, Tbj2, to function as a co-chaperone of TbHsp70.c was investigated.The main objective was to functionally characterize TbHsp70.c to further expand our knowledge of parasite biology. TbHsp70.c and Tbj2 were heterologously expressed and purified and both proteins displayed the ability to suppress aggregation of thermolabile MDH and chemically denatured rhodanese. ATPase assays revealed a 2.8-fold stimulation of the ATPase activity of TbHsp70.c by Tbj2. TbHsp70.c and Tbj2 both demonstrated chaperone activity and Tbj2 functions as a co-chaperone of TbHsp70.c.In vivo heat stress experiments indicated upregulation of the expression levels of TbHsp70.c.
- Full Text:
- Date Issued: 2014
- Authors: Burger, Adélle , Ludewig, Michael H , Boshoff, Aileen
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431155 , vital:72749 , xlink:href="https://doi.org/10.1155/2014/172582"
- Description: The neglected tropical disease, African Trypanosomiasis, is fatal and has a crippling impact on economic development. Heat shock protein 70 (Hsp70) is an important molecular chaperone that is expressed in response to stress and Hsp40 acts as its co-chaperone. These proteins play a wide range of roles in the cell and they are required to assist the parasite as it moves from a cold blooded insect vector to a warm blooded mammalian host. A novel cytosolic Hsp70, from Trypanosoma brucei, TbHsp70.c, contains an acidic substrate binding domain and lacks the C-terminal EEVD motif.The ability of a cytosolic Hsp40 from Trypanosoma brucei J protein 2, Tbj2, to function as a co-chaperone of TbHsp70.c was investigated.The main objective was to functionally characterize TbHsp70.c to further expand our knowledge of parasite biology. TbHsp70.c and Tbj2 were heterologously expressed and purified and both proteins displayed the ability to suppress aggregation of thermolabile MDH and chemically denatured rhodanese. ATPase assays revealed a 2.8-fold stimulation of the ATPase activity of TbHsp70.c by Tbj2. TbHsp70.c and Tbj2 both demonstrated chaperone activity and Tbj2 functions as a co-chaperone of TbHsp70.c.In vivo heat stress experiments indicated upregulation of the expression levels of TbHsp70.c.
- Full Text:
- Date Issued: 2014
Isn’t it time to start thinking about ‘developing’ academic developers in a more systematic way?
- Quinn, Lynn, Vorster, Jo-Anne
- Authors: Quinn, Lynn , Vorster, Jo-Anne
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66546 , vital:28961 , https://doi.org/10.1080/1360144X.2013.879719
- Description: publisher version , There is no defined route to becoming an academic developer. The research on pathways into the field (e.g. Kensington-Miller, Brailsford, and Gossman, 2012; McDonald, 2010; McDonald and Stockley, 2008) shows that in most cases ‘serendipity and chance played a role’ (McDonald, 2010, p. 40). Moreover, induction into academic development (AD) is often ad hoc, haphazard, and informal. Due to the changing higher education (HE) context, the field has grown exponentially and in many countries now plays a central role in institutions. This has generated increased demand for knowledgeable and competent developers that are able to contribute towards solving some vexing problems in contemporary HE. Current recruitment and induction processes of new developers do not necessarily meet this demand. In light of the above, we pose the question: given the changing context of HE and the field of AD, is it not time for us to induct newcomers into the field more systematically? As Kensington-Miller et al. (2012) suggest, we should not leave the induction of the next generation of developers to chance. We suggest that one way of ensuring appropriate induction is through a formal course for developers. Difficulties for newcomers to the field are illustrated by Kensington-Miller et al. (2012) when they report seeking ‘top tips’ at a HERDSA conference. We do not dismiss informal learning at conferences or the role of mentoring, coaching, apprenticeship, and so on, in inducting developers, nor do we minimise the benefits of relatively structured processes such as fellowship programmes, workshops, and postgraduate qualifications in related fields. However, these ways of induction may not offer novices the structured and systematic developmental opportunities needed to become developers able to fulfil varied, complex, and sometimes contradictory roles.
- Full Text: false
- Date Issued: 2014
- Authors: Quinn, Lynn , Vorster, Jo-Anne
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66546 , vital:28961 , https://doi.org/10.1080/1360144X.2013.879719
- Description: publisher version , There is no defined route to becoming an academic developer. The research on pathways into the field (e.g. Kensington-Miller, Brailsford, and Gossman, 2012; McDonald, 2010; McDonald and Stockley, 2008) shows that in most cases ‘serendipity and chance played a role’ (McDonald, 2010, p. 40). Moreover, induction into academic development (AD) is often ad hoc, haphazard, and informal. Due to the changing higher education (HE) context, the field has grown exponentially and in many countries now plays a central role in institutions. This has generated increased demand for knowledgeable and competent developers that are able to contribute towards solving some vexing problems in contemporary HE. Current recruitment and induction processes of new developers do not necessarily meet this demand. In light of the above, we pose the question: given the changing context of HE and the field of AD, is it not time for us to induct newcomers into the field more systematically? As Kensington-Miller et al. (2012) suggest, we should not leave the induction of the next generation of developers to chance. We suggest that one way of ensuring appropriate induction is through a formal course for developers. Difficulties for newcomers to the field are illustrated by Kensington-Miller et al. (2012) when they report seeking ‘top tips’ at a HERDSA conference. We do not dismiss informal learning at conferences or the role of mentoring, coaching, apprenticeship, and so on, in inducting developers, nor do we minimise the benefits of relatively structured processes such as fellowship programmes, workshops, and postgraduate qualifications in related fields. However, these ways of induction may not offer novices the structured and systematic developmental opportunities needed to become developers able to fulfil varied, complex, and sometimes contradictory roles.
- Full Text: false
- Date Issued: 2014
ISSRs indicate that Chromolaena odorata invading southern Africa originates in Jamaica or Cuba
- Paterson, Iain D, Zachariades, Coastas
- Authors: Paterson, Iain D , Zachariades, Coastas
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/406105 , vital:70239 , xlink:href="https://doi.org/10.1016/j.biocontrol.2013.04.005"
- Description: Two biotypes of the invasive alien plant, Chromolaena odorata (L.) R.M. King and Rob. (Asteraceae: Eupatorieae), are recognized in the plant’s introduced distribution. The Asian/West African (A/WA) biotype is present in West and Central Africa, India, Southeast Asia and Oceania, while the southern African (SA) biotype is only present in southern Africa. Biological control using insect natural enemies has been significantly more successful against the A/WA biotype than the SA biotype, suggesting that host plant incompatibility may have resulted in reduced efficacy of biological control agents in southern Africa. Inter-Simple Sequence Repeats (ISSR) were used to identify the origin of the SA biotype as Jamaica or Cuba. The data also confirm that the SA biotype is genetically distinct from the A/WA biotype and that the SA biotype is the result of a separate introduction. Biological control agents for C. odorata in southern Africa should be sourced from Jamaica and Cuba in order to avoid host plant incompatibility problems.
- Full Text:
- Date Issued: 2014
- Authors: Paterson, Iain D , Zachariades, Coastas
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/406105 , vital:70239 , xlink:href="https://doi.org/10.1016/j.biocontrol.2013.04.005"
- Description: Two biotypes of the invasive alien plant, Chromolaena odorata (L.) R.M. King and Rob. (Asteraceae: Eupatorieae), are recognized in the plant’s introduced distribution. The Asian/West African (A/WA) biotype is present in West and Central Africa, India, Southeast Asia and Oceania, while the southern African (SA) biotype is only present in southern Africa. Biological control using insect natural enemies has been significantly more successful against the A/WA biotype than the SA biotype, suggesting that host plant incompatibility may have resulted in reduced efficacy of biological control agents in southern Africa. Inter-Simple Sequence Repeats (ISSR) were used to identify the origin of the SA biotype as Jamaica or Cuba. The data also confirm that the SA biotype is genetically distinct from the A/WA biotype and that the SA biotype is the result of a separate introduction. Biological control agents for C. odorata in southern Africa should be sourced from Jamaica and Cuba in order to avoid host plant incompatibility problems.
- Full Text:
- Date Issued: 2014
Liberation movements in power: party and state in southern Africa
- Authors: Helliker, Kirk D
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144688 , vital:38370 , DOI: 10.1080/21528586.2014.960705
- Description: In Liberation movements in power, Roger Southall provides a rich and refined account of political transformation in three ex-settler colonies in southern Africa, namely, South Africa, Namibia and Zimbabwe. In particular, he focuses on their former hegemonic national liberation movements, namely, the African National Congress (ANC) in South Africa, the South West African People’s Organisation (SWAPO) in Namibia and the Zimbabwe African National Union (ZANU) – now ZANU-Patriotic Front (ZANU-PF) – in Zimbabwe, their metamorphism into political parties and party machines, and their ‘capture’ of state power as the dominant political party subsequent to the end of white settler colonialism and the emergence of non-racial democracy. The general conclusion is that democratic ideals and procedures have become subordinated to the dictates of authoritarian restructuring.
- Full Text:
- Date Issued: 2014
- Authors: Helliker, Kirk D
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144688 , vital:38370 , DOI: 10.1080/21528586.2014.960705
- Description: In Liberation movements in power, Roger Southall provides a rich and refined account of political transformation in three ex-settler colonies in southern Africa, namely, South Africa, Namibia and Zimbabwe. In particular, he focuses on their former hegemonic national liberation movements, namely, the African National Congress (ANC) in South Africa, the South West African People’s Organisation (SWAPO) in Namibia and the Zimbabwe African National Union (ZANU) – now ZANU-Patriotic Front (ZANU-PF) – in Zimbabwe, their metamorphism into political parties and party machines, and their ‘capture’ of state power as the dominant political party subsequent to the end of white settler colonialism and the emergence of non-racial democracy. The general conclusion is that democratic ideals and procedures have become subordinated to the dictates of authoritarian restructuring.
- Full Text:
- Date Issued: 2014
Life satisfaction and education in South Africa: Investigating the role of attainment and the likelihood of education as a positional good
- Authors: Botha, Ferdi
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396091 , vital:69149 , xlink:href="https://doi.org/10.1007/s11205-013-0452-2"
- Description: This paper explores various dynamics in the relationship between life satisfaction and education in South Africa using the 2008 National Income Dynamics Survey. The results indicate a strong positive association between educational attainment and individual satisfaction with life, which is true in the overall sample and for men and women. This positive relationship also holds for Black and Coloured individuals, but is insignificant in the Asian and White samples. Evidence indicates that education is a positional good, in that people who have attained more than the mean level of education in their relevant cluster are significantly more satisfied with life compared to those possessing less than the mean education.
- Full Text:
- Date Issued: 2014
- Authors: Botha, Ferdi
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396091 , vital:69149 , xlink:href="https://doi.org/10.1007/s11205-013-0452-2"
- Description: This paper explores various dynamics in the relationship between life satisfaction and education in South Africa using the 2008 National Income Dynamics Survey. The results indicate a strong positive association between educational attainment and individual satisfaction with life, which is true in the overall sample and for men and women. This positive relationship also holds for Black and Coloured individuals, but is insignificant in the Asian and White samples. Evidence indicates that education is a positional good, in that people who have attained more than the mean level of education in their relevant cluster are significantly more satisfied with life compared to those possessing less than the mean education.
- Full Text:
- Date Issued: 2014
Losing, using, refusing, cruising: first-generation South African women academics narrate the complexity of marginality
- Idahosa, Grace E, Vincent, Louise
- Authors: Idahosa, Grace E , Vincent, Louise
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141820 , vital:38007 , DOI: 10.1080/10130950.2014.874766
- Description: In this article we ask how senior academic women in South Africa narrate their experience of being ‘outside in’ the teaching machine. Wide research literature documents the gross underrepresentation of women in senior positions in the academy. It has been argued that intertwined sexist, patriarchal and phallocentric knowledges and practices in academic institutions produce various forms of discrimination, inequality, oppression and marginalisation. Academic women report feeling invisible and retreating to the margins so as to avoid victimisation and discrimination. Others have pointed to the tension between the ‘tenure clock’ and ‘biological clock’ as a source of anxiety. However, experiences of academic women are not identical. In the context of studies showing the importance of existing personal and social resources, prior experience and having mentors and role models in the negotiation of inequality and discrimination, we document the narratives of women academics who are the first in their families to graduate with a university degree.
- Full Text:
- Date Issued: 2014
- Authors: Idahosa, Grace E , Vincent, Louise
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141820 , vital:38007 , DOI: 10.1080/10130950.2014.874766
- Description: In this article we ask how senior academic women in South Africa narrate their experience of being ‘outside in’ the teaching machine. Wide research literature documents the gross underrepresentation of women in senior positions in the academy. It has been argued that intertwined sexist, patriarchal and phallocentric knowledges and practices in academic institutions produce various forms of discrimination, inequality, oppression and marginalisation. Academic women report feeling invisible and retreating to the margins so as to avoid victimisation and discrimination. Others have pointed to the tension between the ‘tenure clock’ and ‘biological clock’ as a source of anxiety. However, experiences of academic women are not identical. In the context of studies showing the importance of existing personal and social resources, prior experience and having mentors and role models in the negotiation of inequality and discrimination, we document the narratives of women academics who are the first in their families to graduate with a university degree.
- Full Text:
- Date Issued: 2014
Low-cost housing developments in South Africa miss the opportunities for household level urban greening
- Shackleton, Charlie M, Hebinck, Paul, Kaoma, Humphrey, Chishaleshale, Mwale, Chinyimba, Abby, Shackleton, Sheona E, Gambiza, James, Gumbo, Davison
- Authors: Shackleton, Charlie M , Hebinck, Paul , Kaoma, Humphrey , Chishaleshale, Mwale , Chinyimba, Abby , Shackleton, Sheona E , Gambiza, James , Gumbo, Davison
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180967 , vital:43677 , xlink:href="https://doi.org/10.1016/j.landusepol.2013.10.002"
- Description: Most developing countries of the world are experiencing large-scale migration from rural to urban areas. Many new migrants end up in low-cost or informal areas and slums with attendant environmental concerns. One dimension of improved urban sustainability is the provision of green spaces and trees. Whilst many countries have urban greening programmes for public spaces and streets, few have considered the status and potential contribution of trees from resident's own gardens. This paper reports firstly on the policy environment for urban forestry and greening in South Africa and secondly on the maintenance, use and appreciation of trees on private homesteads of residents of new and older low-income suburbs as well as informal housing areas from three small towns in South Africa. In particular we examine if the most recent centrally planned and built low-income housing schemes (called RDP suburbs in South Africa) have considered and incorporated plans or spaces for urban greenery in peoples’ homesteads. We found that broad environmental and sustainability concerns and statements are common in urban development and housing policies, but specific guidelines for implementation are generally absent. More specifically, urban forestry and tree planting are rarely mentioned in the broader land use and environmental policies other than the national forest act and subsequent regulations, but even there it is relatively superficial. In the study towns the prevalence, density and number of species of trees was lowest in the new RDP suburbs relative to the township and informal areas. Consequently, the contribution of tree products to local livelihoods was also lower in the RDP areas. Yet there were no differences in the level of appreciation of the value and intangible benefits of trees between residents from the three different suburbs. This shows that the failure to plan for and accommodate trees in new low-cost housing developments is missing an opportunity to improve overall urban sustainability and liveability and constraining the potential flows of tangible and intangible benefits to urban residents. Making opportunities for such in older suburbs is challenging because of space limitations and cost implications of retrospective provisions, but incorporation into plans for new low-cost housing development should be possible.
- Full Text:
- Date Issued: 2014
- Authors: Shackleton, Charlie M , Hebinck, Paul , Kaoma, Humphrey , Chishaleshale, Mwale , Chinyimba, Abby , Shackleton, Sheona E , Gambiza, James , Gumbo, Davison
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180967 , vital:43677 , xlink:href="https://doi.org/10.1016/j.landusepol.2013.10.002"
- Description: Most developing countries of the world are experiencing large-scale migration from rural to urban areas. Many new migrants end up in low-cost or informal areas and slums with attendant environmental concerns. One dimension of improved urban sustainability is the provision of green spaces and trees. Whilst many countries have urban greening programmes for public spaces and streets, few have considered the status and potential contribution of trees from resident's own gardens. This paper reports firstly on the policy environment for urban forestry and greening in South Africa and secondly on the maintenance, use and appreciation of trees on private homesteads of residents of new and older low-income suburbs as well as informal housing areas from three small towns in South Africa. In particular we examine if the most recent centrally planned and built low-income housing schemes (called RDP suburbs in South Africa) have considered and incorporated plans or spaces for urban greenery in peoples’ homesteads. We found that broad environmental and sustainability concerns and statements are common in urban development and housing policies, but specific guidelines for implementation are generally absent. More specifically, urban forestry and tree planting are rarely mentioned in the broader land use and environmental policies other than the national forest act and subsequent regulations, but even there it is relatively superficial. In the study towns the prevalence, density and number of species of trees was lowest in the new RDP suburbs relative to the township and informal areas. Consequently, the contribution of tree products to local livelihoods was also lower in the RDP areas. Yet there were no differences in the level of appreciation of the value and intangible benefits of trees between residents from the three different suburbs. This shows that the failure to plan for and accommodate trees in new low-cost housing developments is missing an opportunity to improve overall urban sustainability and liveability and constraining the potential flows of tangible and intangible benefits to urban residents. Making opportunities for such in older suburbs is challenging because of space limitations and cost implications of retrospective provisions, but incorporation into plans for new low-cost housing development should be possible.
- Full Text:
- Date Issued: 2014
Mini-review on the use of liquid membranes in the extraction of platinum group metals from mining and metal refinery wastewaters/side-streams
- Moyo, Francis, Tandlich, Roman
- Authors: Moyo, Francis , Tandlich, Roman
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/75960 , vital:30487 , DOI: 10.4172/2155-6199.1000228
- Description: The current mini-review focuses on the use of liquid membranes in the platinum group metal (PGM/PGMs) extraction from various types of wastewaters to prevent environmental pollution; and for the metal recovery to address the scarcity of the PGMs in the industrial cycles. The bulk liquid membranes have been used to the extracted PGMs from the (acidic) aqueous media with recoveries of up to 96.3 ± 2.5% of the original PGM amount. The extraction time generally ranges from 2 to 24 hours. The bulk membrane liquid in the PGM extraction will depend on the covalent structure of the extractant, the feed phase PGM concentration and the complex of the PGM in question that is actually extracted from the aqueous environment. The advantages of this type of liquid membrane include its operational simplicity, but the disadvantages include limited possibility to improve the extraction performance of the system. Literature data are encouraging as they indicate that extraction of PGMs from mining and metal-refinery side-streams does not suffer from interference from metal contaminants that are commonly found in the mining and metal refinery side-streams, e.g. iron. Thus further research should focus on the application of ELM to extraction of PGMs from said wastewaters and major research drive should focus on the use of the Taylorvortex column and the non-Newtonian ELMs. With the supported liquid membranes, 78-82% of the original PGM content could be recovered from model side-streams. The selectivity of the extraction for individual PGMs can be controlled by the extractant used.
- Full Text:
- Date Issued: 2014
- Authors: Moyo, Francis , Tandlich, Roman
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/75960 , vital:30487 , DOI: 10.4172/2155-6199.1000228
- Description: The current mini-review focuses on the use of liquid membranes in the platinum group metal (PGM/PGMs) extraction from various types of wastewaters to prevent environmental pollution; and for the metal recovery to address the scarcity of the PGMs in the industrial cycles. The bulk liquid membranes have been used to the extracted PGMs from the (acidic) aqueous media with recoveries of up to 96.3 ± 2.5% of the original PGM amount. The extraction time generally ranges from 2 to 24 hours. The bulk membrane liquid in the PGM extraction will depend on the covalent structure of the extractant, the feed phase PGM concentration and the complex of the PGM in question that is actually extracted from the aqueous environment. The advantages of this type of liquid membrane include its operational simplicity, but the disadvantages include limited possibility to improve the extraction performance of the system. Literature data are encouraging as they indicate that extraction of PGMs from mining and metal-refinery side-streams does not suffer from interference from metal contaminants that are commonly found in the mining and metal refinery side-streams, e.g. iron. Thus further research should focus on the application of ELM to extraction of PGMs from said wastewaters and major research drive should focus on the use of the Taylorvortex column and the non-Newtonian ELMs. With the supported liquid membranes, 78-82% of the original PGM content could be recovered from model side-streams. The selectivity of the extraction for individual PGMs can be controlled by the extractant used.
- Full Text:
- Date Issued: 2014
Modelling annual evapotranspiration in a semi-arid, African savanna: functional convergence theory, MODIS LAI and the Penman–Monteith equation
- Palmer, Anthony R, Weideman, Craig I, Finca, Andiswa, Everson, Colin S, Hanan, Niall P, Ellery, William F N
- Authors: Palmer, Anthony R , Weideman, Craig I , Finca, Andiswa , Everson, Colin S , Hanan, Niall P , Ellery, William F N
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144387 , vital:38341 , DOI: 10.2989/10220119.2014.931305
- Description: Accurately measuring evapotranspiration (ET) is essential if we are to derive reasonable estimates of production and water use for semi-arid savannas. Estimates of ET are also important in defining the health of an ecosystem and the quantity of water used by the vegetation when preparing a catchment-scale water balance. We derived ET0 from an automatic weather station 30 km west of Skukuza, Kruger National Park, South Africa using the Penman– Monteith equation, and then used the MODIS LAI to inform the model of canopy phenological dynamics. This result was compared with 173 days of ET measurements from the eddy covariance (ETec) system near Skukuza in 2007 as well as from the ET recorded by a large-aperture scintillometer at the same site in 2005. The model compared favourably with both sets of measured data and, when used independently of the eddy covariance data, ETMODIS predicted an annual ET of 378 mm in 2007 for the semi-arid savanna around the Skukuza flux site.
- Full Text:
- Date Issued: 2014
- Authors: Palmer, Anthony R , Weideman, Craig I , Finca, Andiswa , Everson, Colin S , Hanan, Niall P , Ellery, William F N
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144387 , vital:38341 , DOI: 10.2989/10220119.2014.931305
- Description: Accurately measuring evapotranspiration (ET) is essential if we are to derive reasonable estimates of production and water use for semi-arid savannas. Estimates of ET are also important in defining the health of an ecosystem and the quantity of water used by the vegetation when preparing a catchment-scale water balance. We derived ET0 from an automatic weather station 30 km west of Skukuza, Kruger National Park, South Africa using the Penman– Monteith equation, and then used the MODIS LAI to inform the model of canopy phenological dynamics. This result was compared with 173 days of ET measurements from the eddy covariance (ETec) system near Skukuza in 2007 as well as from the ET recorded by a large-aperture scintillometer at the same site in 2005. The model compared favourably with both sets of measured data and, when used independently of the eddy covariance data, ETMODIS predicted an annual ET of 378 mm in 2007 for the semi-arid savanna around the Skukuza flux site.
- Full Text:
- Date Issued: 2014
Necrophiliac Narration and the Business of Friends: Damon Galgut’s The Good Doctor
- Authors: Marais, Mike
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144159 , vital:38316 , DOI: 10.1080/17533171.2014.918406
- Description: Set in the period following South Africa’s first democratic elections, Damon Galgut’s The Good Doctor traces the friendship that develops between two doctors working at a rural hospital. While it does not deal overtly with the politics of the “new” South Africa, the novel’s treatment of friendship, which cuts across the distinction between the private and the public, reflects obliquely on the nature of the emerging democratic dispensation. In this paper, I explore the link that Galgut constructs between friendship and community, and argue that his portrayal of the former points to the possibility of a form of community that is premised on a “common strangeness.”
- Full Text:
- Date Issued: 2014
- Authors: Marais, Mike
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144159 , vital:38316 , DOI: 10.1080/17533171.2014.918406
- Description: Set in the period following South Africa’s first democratic elections, Damon Galgut’s The Good Doctor traces the friendship that develops between two doctors working at a rural hospital. While it does not deal overtly with the politics of the “new” South Africa, the novel’s treatment of friendship, which cuts across the distinction between the private and the public, reflects obliquely on the nature of the emerging democratic dispensation. In this paper, I explore the link that Galgut constructs between friendship and community, and argue that his portrayal of the former points to the possibility of a form of community that is premised on a “common strangeness.”
- Full Text:
- Date Issued: 2014
Occurrence of larval fishes in a rocky shore-associated nursery area in temperate South Africa, with emphasis on temperature-related growth in dominant Sparidae
- Strydom, Nadine A, Booth, Anthony J, McLachlan, A
- Authors: Strydom, Nadine A , Booth, Anthony J , McLachlan, A
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125342 , vital:35774 , https://doi.10.2989/1814232X.2014.899269
- Description: Larval fishes were studied in Shark Bay on the warm, temperate south-east coast of South Africa. The bay is a small, shallow, subtidal area associated with a rocky shore. Sampling took place fortnightly for a period of one year (September 2004–August 2005) to assess composition, abundance and growth of fishes. The objectives of the study were to assess the extent of use of this habitat type by larvae throughout the year and to ascertain what temperature advantages this relatively warm habitat could have on growth of dominant species. A total of 10 fish families, represented by 16 taxa, was collected using a specially modified beach seine net (mesh aperture 500 μm). Shark Bay was utilised extensively by Diplodus capensis and Sarpa salpa and to a lesser extent by Clinus supercilious, Liza spp. and Mugil cephalus. Mean catch per unit effort (CPUE) of larvae was high (>500 larvae per net haul), peaking at ~7 500 larvae in a single haul that consisted mostly of postflexion-stage Sparidae. There was a weak, negative correlation (−0.24) between temperature and overall CPUE, which reflected either the seasonality or protracted nature of spawning by the species occurring in the bay. There was no significant difference in CPUE between the moon phases sampled on the spring tides in this study. Shark Bay was dominated by postflexionstage larvae, consisting in particular of species common to tide pools during the juvenile stage. Certain species were sampled for only short periods during the year. The year-round occurrence and high abundance of the two dominant species indicate that Shark Bay represents an important nursery habitat for the completion of the larval phase. These species exhibited exponential growth that lagged behind small increases in temperature, highlighting the importance of access to shallow, warm habitat that allows larval growth to increase, leading to earlier settlement into juvenile habitat and thereby reducing the pelagic larval duration.
- Full Text:
- Date Issued: 2014
- Authors: Strydom, Nadine A , Booth, Anthony J , McLachlan, A
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125342 , vital:35774 , https://doi.10.2989/1814232X.2014.899269
- Description: Larval fishes were studied in Shark Bay on the warm, temperate south-east coast of South Africa. The bay is a small, shallow, subtidal area associated with a rocky shore. Sampling took place fortnightly for a period of one year (September 2004–August 2005) to assess composition, abundance and growth of fishes. The objectives of the study were to assess the extent of use of this habitat type by larvae throughout the year and to ascertain what temperature advantages this relatively warm habitat could have on growth of dominant species. A total of 10 fish families, represented by 16 taxa, was collected using a specially modified beach seine net (mesh aperture 500 μm). Shark Bay was utilised extensively by Diplodus capensis and Sarpa salpa and to a lesser extent by Clinus supercilious, Liza spp. and Mugil cephalus. Mean catch per unit effort (CPUE) of larvae was high (>500 larvae per net haul), peaking at ~7 500 larvae in a single haul that consisted mostly of postflexion-stage Sparidae. There was a weak, negative correlation (−0.24) between temperature and overall CPUE, which reflected either the seasonality or protracted nature of spawning by the species occurring in the bay. There was no significant difference in CPUE between the moon phases sampled on the spring tides in this study. Shark Bay was dominated by postflexionstage larvae, consisting in particular of species common to tide pools during the juvenile stage. Certain species were sampled for only short periods during the year. The year-round occurrence and high abundance of the two dominant species indicate that Shark Bay represents an important nursery habitat for the completion of the larval phase. These species exhibited exponential growth that lagged behind small increases in temperature, highlighting the importance of access to shallow, warm habitat that allows larval growth to increase, leading to earlier settlement into juvenile habitat and thereby reducing the pelagic larval duration.
- Full Text:
- Date Issued: 2014
Ocean warming affects the distribution and abundance of resident fishes by changing their reproductive scope
- Potts, Warren M, Booth, Anthony J, Richardson, Timothy J, Sauer, Warwick H H
- Authors: Potts, Warren M , Booth, Anthony J , Richardson, Timothy J , Sauer, Warwick H H
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125352 , vital:35775 , https://doi.10.1007/s11160-013-9329-3
- Description: With ocean warming predicted globally, one of the mechanisms driving distributional shifts and changes in the abundance of resident fishes is reproductive output. The relationship between sea surface temperature and the reproductive activity of a eurythermic, resident coastal species, blacktail seabream Diplodus sargus capensis, was examined in the ‘‘ocean warming’’ hotspot of the northern Benguela. Reproductive activity was found to be restricted to periods when the water temperature dropped below 20 _C. A metadata analysis conducted on the D. sargus sub-species complex similarly showed that reproductive activity was restricted to temperatures between 15 and 20 _C, regardless of the range in ambient water temperature. Based on these findings and using satellite derived SST information, we examined D. s. capensis’s total and seasonal ‘‘reproductive scope’’ that is defined as either the area suitable for spawning each year or the duration of its potential spawning season at a fixed geographical locality, respectively. Trends were examined over the last three decades. Reproductive scope by area was found to be shrinking at a rate of 7 % per decade in southern Angola and expanding at a rate of 6 % per decade in northern Namibia. Reproductive scope by season decreased by 1.05 months per decade in Namibe, southern Angola and increased by 0.76 months per decade in Hentiesbaai, northern Namibia. Changes in reproductive scope may be a driving mechanism of distributional shifts in resident fishes, although the rate of the shifts is likely to be slow. More importantly, changes in reproductive scope will not be uniform throughout fish distributions and will most likely result in heterogeneous variations in fish abundance.
- Full Text:
- Date Issued: 2014
- Authors: Potts, Warren M , Booth, Anthony J , Richardson, Timothy J , Sauer, Warwick H H
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125352 , vital:35775 , https://doi.10.1007/s11160-013-9329-3
- Description: With ocean warming predicted globally, one of the mechanisms driving distributional shifts and changes in the abundance of resident fishes is reproductive output. The relationship between sea surface temperature and the reproductive activity of a eurythermic, resident coastal species, blacktail seabream Diplodus sargus capensis, was examined in the ‘‘ocean warming’’ hotspot of the northern Benguela. Reproductive activity was found to be restricted to periods when the water temperature dropped below 20 _C. A metadata analysis conducted on the D. sargus sub-species complex similarly showed that reproductive activity was restricted to temperatures between 15 and 20 _C, regardless of the range in ambient water temperature. Based on these findings and using satellite derived SST information, we examined D. s. capensis’s total and seasonal ‘‘reproductive scope’’ that is defined as either the area suitable for spawning each year or the duration of its potential spawning season at a fixed geographical locality, respectively. Trends were examined over the last three decades. Reproductive scope by area was found to be shrinking at a rate of 7 % per decade in southern Angola and expanding at a rate of 6 % per decade in northern Namibia. Reproductive scope by season decreased by 1.05 months per decade in Namibe, southern Angola and increased by 0.76 months per decade in Hentiesbaai, northern Namibia. Changes in reproductive scope may be a driving mechanism of distributional shifts in resident fishes, although the rate of the shifts is likely to be slow. More importantly, changes in reproductive scope will not be uniform throughout fish distributions and will most likely result in heterogeneous variations in fish abundance.
- Full Text:
- Date Issued: 2014
Ocean warming hotspots provide early warning laboratories for climate change impacts
- Pecl, Gretta T, Hobday, Alistair J, Frusher, Stewart, Sauer, Warwick H H, Bates, Amanda E
- Authors: Pecl, Gretta T , Hobday, Alistair J , Frusher, Stewart , Sauer, Warwick H H , Bates, Amanda E
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125363 , vital:35776 , https://doi.10.1007/s11160-014-9355-9
- Description: A growing literature describes a wide range of negative impacts of climate change on marine resources and the people and communities they support, including species range changes, changes in productivity of fisheries and declines in economic performance (Doney et al. 2012; Poloczanska et al. 2013). These impacts, many of which are projected to increase in future, are compounded by growing pressures on marine resources (Halpern et al. 2008; Maxwell et al. 2013). An estimated 260 million people are involved directly or indirectly in global marine fisheries (Teh and Sumaila 2013) with many of the resources for capture fisheries already fully (&57 % in 2009) or over exploited (30 %) (FAO 2012). Nevertheless, production of marine resources will need to increase to accommodate the demands of a growing population, and the impacts of climate change on food security will need to be minimised (FAO 2009). Identifying opportunities and threats, and developing adaptation options in response to climate change impacts in the marine realm, is essential for optimising the benefits that society can continue to derive from the goods and services provided by marine resources.
- Full Text:
- Date Issued: 2014
- Authors: Pecl, Gretta T , Hobday, Alistair J , Frusher, Stewart , Sauer, Warwick H H , Bates, Amanda E
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125363 , vital:35776 , https://doi.10.1007/s11160-014-9355-9
- Description: A growing literature describes a wide range of negative impacts of climate change on marine resources and the people and communities they support, including species range changes, changes in productivity of fisheries and declines in economic performance (Doney et al. 2012; Poloczanska et al. 2013). These impacts, many of which are projected to increase in future, are compounded by growing pressures on marine resources (Halpern et al. 2008; Maxwell et al. 2013). An estimated 260 million people are involved directly or indirectly in global marine fisheries (Teh and Sumaila 2013) with many of the resources for capture fisheries already fully (&57 % in 2009) or over exploited (30 %) (FAO 2012). Nevertheless, production of marine resources will need to increase to accommodate the demands of a growing population, and the impacts of climate change on food security will need to be minimised (FAO 2009). Identifying opportunities and threats, and developing adaptation options in response to climate change impacts in the marine realm, is essential for optimising the benefits that society can continue to derive from the goods and services provided by marine resources.
- Full Text:
- Date Issued: 2014
Ocean warming, a rapid distributional shift, and the hybridization of a coastal fish species
- Potts, Warren M, Henriques, Romina, Santos, Carmen V D, Munnik, Kate, Ansorge, Isabelle J, Dufois, Francois, Sauer, Warwick H H, Booth, Anthony J, Kirchner, Carola, Sauer, Warwick, Shaw, Paul W
- Authors: Potts, Warren M , Henriques, Romina , Santos, Carmen V D , Munnik, Kate , Ansorge, Isabelle J , Dufois, Francois , Sauer, Warwick H H , Booth, Anthony J , Kirchner, Carola , Sauer, Warwick , Shaw, Paul W
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125375 , vital:35777 , https://doi.10.1111/gcb.12612
- Description: Despite increasing awareness of large-scale climate-driven distribution shifts in the marine environment, no study has linked rapid ocean warming to a shift in distribution and consequent hybridization of a marine fish species. This study describes rapid warming (0.8 °C per decade) in the coastal waters of the Angola-Benguela Frontal Zone over the last three decades and a concomitant shift by a temperature sensitive coastal fish species (Argyrosomus coronus) southward from Angola into Namibia. In this context, rapid shifts in distribution across Economic Exclusive Zones will complicate the management of fishes, particularly when there is a lack of congruence in the fisheries policy between nations. Evidence for recent hybridization between A. coronus and a congener, A. inodorus, indicate that the rapid shift in distribution of A. coronus has placed adults of the two species in contact during their spawning events. Ocean warming may therefore revert established species isolation mechanisms and alter the evolutionary history of fishes. While the consequences of the hybridization on the production of the resource remain unclear, this will most likely introduce additional layers of complexity to their management.
- Full Text:
- Date Issued: 2014
- Authors: Potts, Warren M , Henriques, Romina , Santos, Carmen V D , Munnik, Kate , Ansorge, Isabelle J , Dufois, Francois , Sauer, Warwick H H , Booth, Anthony J , Kirchner, Carola , Sauer, Warwick , Shaw, Paul W
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125375 , vital:35777 , https://doi.10.1111/gcb.12612
- Description: Despite increasing awareness of large-scale climate-driven distribution shifts in the marine environment, no study has linked rapid ocean warming to a shift in distribution and consequent hybridization of a marine fish species. This study describes rapid warming (0.8 °C per decade) in the coastal waters of the Angola-Benguela Frontal Zone over the last three decades and a concomitant shift by a temperature sensitive coastal fish species (Argyrosomus coronus) southward from Angola into Namibia. In this context, rapid shifts in distribution across Economic Exclusive Zones will complicate the management of fishes, particularly when there is a lack of congruence in the fisheries policy between nations. Evidence for recent hybridization between A. coronus and a congener, A. inodorus, indicate that the rapid shift in distribution of A. coronus has placed adults of the two species in contact during their spawning events. Ocean warming may therefore revert established species isolation mechanisms and alter the evolutionary history of fishes. While the consequences of the hybridization on the production of the resource remain unclear, this will most likely introduce additional layers of complexity to their management.
- Full Text:
- Date Issued: 2014
On the viability of pro-active automated PII breach detection: A South African case study
- Swart, Ignus, Irwin, Barry V W, Grobler, Marthie
- Authors: Swart, Ignus , Irwin, Barry V W , Grobler, Marthie
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430235 , vital:72676 , https://doi.org/10.1145/2664591.2664600
- Description: Various reasons exist why certain types of information is deemed personal both by legislation and society. While crimes such as identity theft and impersonation have always been in existence, the rise of the internet and social media has exacerbated the problem. South Africa has recently joined the growing ranks of countries passing legislation to ensure the privacy of certain types of data. As is the case with most implemented security enforcement systems, most appointed privacy regulators operate in a reactive way. While this is a completely acceptable method of operation, it is not the most efficient. Research has shown that most data leaks containing personal information remains available for more than a month on average before being detected and reported. Quite often the data is discovered by a third party who selects to notify the responsible organisation but can just as easily copy the data and make use of it. This paper will display the potential benefit a privacy regulator can expect to see by implementing pro-active detection of electronic personally identifiable information (PII). Adopting pro-active detection of PII exposed on public networks can potentially contribute to a significant reduction in exposure time. The results discussed in this paper were obtained by means of experimentation on a custom created PII detection system.
- Full Text:
- Date Issued: 2014
- Authors: Swart, Ignus , Irwin, Barry V W , Grobler, Marthie
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430235 , vital:72676 , https://doi.org/10.1145/2664591.2664600
- Description: Various reasons exist why certain types of information is deemed personal both by legislation and society. While crimes such as identity theft and impersonation have always been in existence, the rise of the internet and social media has exacerbated the problem. South Africa has recently joined the growing ranks of countries passing legislation to ensure the privacy of certain types of data. As is the case with most implemented security enforcement systems, most appointed privacy regulators operate in a reactive way. While this is a completely acceptable method of operation, it is not the most efficient. Research has shown that most data leaks containing personal information remains available for more than a month on average before being detected and reported. Quite often the data is discovered by a third party who selects to notify the responsible organisation but can just as easily copy the data and make use of it. This paper will display the potential benefit a privacy regulator can expect to see by implementing pro-active detection of electronic personally identifiable information (PII). Adopting pro-active detection of PII exposed on public networks can potentially contribute to a significant reduction in exposure time. The results discussed in this paper were obtained by means of experimentation on a custom created PII detection system.
- Full Text:
- Date Issued: 2014
Ontogenetic and seasonal shifts in the diet of Diplodus cervinus hottentotus (Pisces: Sparidae) in southern Angola
- Winkler, Alexander C, Santos, Carmen V D, Potts, Warren M
- Authors: Winkler, Alexander C , Santos, Carmen V D , Potts, Warren M
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125452 , vital:35784 , https://doi.10.2989/1814232X.2014.951392
- Description: Fishes of the family Sparidae occupy a diverse range of trophic niches, from herbivores to generalist omnivores and specialist predators (Hanel and Tsigenopoulos 2011). Feeding specialisation in this family is facilitated by diversity in tooth type and anterior jaw arrangement (Vandewalle et al. 1995). Other fish families, such as Cyprinidae and Labridae, have developed crushing pharyngeal teeth to process their food. Sparids, however, have retained a simple pharyngeal tooth arrangement and instead have developed molariform teeth to process hard-shelled molluscs and invertebrate prey. Hanel and Tsigenopoulos (2011) suggested that this alternate strategy is a major factor facilitating the trophic diversity in sparid fishes.
- Full Text:
- Date Issued: 2014
- Authors: Winkler, Alexander C , Santos, Carmen V D , Potts, Warren M
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125452 , vital:35784 , https://doi.10.2989/1814232X.2014.951392
- Description: Fishes of the family Sparidae occupy a diverse range of trophic niches, from herbivores to generalist omnivores and specialist predators (Hanel and Tsigenopoulos 2011). Feeding specialisation in this family is facilitated by diversity in tooth type and anterior jaw arrangement (Vandewalle et al. 1995). Other fish families, such as Cyprinidae and Labridae, have developed crushing pharyngeal teeth to process their food. Sparids, however, have retained a simple pharyngeal tooth arrangement and instead have developed molariform teeth to process hard-shelled molluscs and invertebrate prey. Hanel and Tsigenopoulos (2011) suggested that this alternate strategy is a major factor facilitating the trophic diversity in sparid fishes.
- Full Text:
- Date Issued: 2014
Optical nonlinearities and photophysicochemical behaviour of green and blue forms of lutetium bisphthalocyanines
- Sekhosana, Kutloana Edith, Amuhaya, Edith, Mack, John, Nyokong, Tebello
- Authors: Sekhosana, Kutloana Edith , Amuhaya, Edith , Mack, John , Nyokong, Tebello
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241606 , vital:50954 , xlink:href="https://doi.org/10.1039/C4TC00505H"
- Description: A rare earth sandwich-type phthalocyanine: bis-{2,3,9,10,16,17,23,24-octa(4-tert-butylphenoxy) phthalocyaninato} lutetium(III) has been synthesized. The photophysical and nonlinear optical behavior of both the “green” and “blue” forms ([LuIIIPc2] and [LuIIIPc2]−, respectively) of the complex have been investigated. High triplet state and singlet oxygen quantum yield values were obtained for the neutral blue form which contains no unpaired electrons. Relatively high third order susceptibility and hyperpolarizability values of the order of 10−10 and 10−28 esu were obtained for both the green and blue forms, respectively. A very low threshold intensity of 0.00051 J cm−2 was obtained for the blue form. Hence the complex shows promise for non-linear optical applications.
- Full Text:
- Date Issued: 2014
- Authors: Sekhosana, Kutloana Edith , Amuhaya, Edith , Mack, John , Nyokong, Tebello
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241606 , vital:50954 , xlink:href="https://doi.org/10.1039/C4TC00505H"
- Description: A rare earth sandwich-type phthalocyanine: bis-{2,3,9,10,16,17,23,24-octa(4-tert-butylphenoxy) phthalocyaninato} lutetium(III) has been synthesized. The photophysical and nonlinear optical behavior of both the “green” and “blue” forms ([LuIIIPc2] and [LuIIIPc2]−, respectively) of the complex have been investigated. High triplet state and singlet oxygen quantum yield values were obtained for the neutral blue form which contains no unpaired electrons. Relatively high third order susceptibility and hyperpolarizability values of the order of 10−10 and 10−28 esu were obtained for both the green and blue forms, respectively. A very low threshold intensity of 0.00051 J cm−2 was obtained for the blue form. Hence the complex shows promise for non-linear optical applications.
- Full Text:
- Date Issued: 2014