Shoprite Checkers National Treasurer's report
- Authors: SACCAWU
- Date: 2007
- Subjects: SACCAWU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/153853 , vital:39530
- Description: Comrades, this historical 3rd National Summit is convened at a time when the National Democratic Revolution is under attack left, right and centre. We have recently held an ANC Policy Conference; SACP National Congress and COSATU Central Committee, as well as SACCAWU National Bargaining Conference. These Alliance meetings took a number of resolutions for implementation. One has observed a very sorry state of affairs in that some shopstewards who are seen to be very prominent in Shoprite meetings, do not attend SACCAWU structures, let alone COSATU, ANC & SACP structures. This Summit will have to discuss on how we are to revive structures at Shoprite and participation in the aforementioned structures.
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- Date Issued: 2007
Submerged membrane bioreactor and secondary digestion in the treatment of wine distillery waste: Part II: the effect of fungal pre-treatment on wine distillery wastewater digestion
- Authors: Melamane, Xolisa L , Strong, Peter James , Tandlich, Roman , Burgess, Jo E
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76150 , vital:30514 , https://www.prt-parlar.de/download_feb_2007/
- Description: The effect of fungal pre-treatment using Trametes pubescens on the anaerobic digestion ultrafiltration treatment of wine distillery wastewater (WDW) was studied. The downstream biological treatment system, consisting of four individual reactors, was operated for 30 days. pH buffering was achieved by mixing the pre-treated system feed with CaCO3 and K2HPO4; this proved significant for optimum performance of the system in removal of soluble chemical oxygen demand (CODS). The experimental system was shown to eliminate an average of 86 (± 4) % of CODS present in the pre-treated WDW. Treatment in a submerged membrane bioreactor (SMBR) and subsequent secondary digester, together with pH buffering using CaCO3 and K2HPO4, led to the stabilisation of CODS removal. The residual CODS levels in the final effluent were approximately 400 mg/l, significantly lower than the concentrations observed when treating raw WDW, indicating that fungal pre-treatment might have provided additional nutrients for removal of recalcitrant components of the wastewater. The resulting effluent of the system is rich in nitrates and phosphates. Together with the residual organic content it might be used as a fertiliser. Alternatively, if water management of the wine distillery is an issue, a membrane process, such as reverse osmosis or nanofiltration could be applied to bring the parameters of the water to meet the technological needs.
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- Date Issued: 2007
The biology and laboratory host range of the weevil, Listronotus marginicollis (Hustache)(Coleoptera: Curculionidae), a natural enemy of the invasive aquatic weed, parrot's feather, Myriophyllum aquaticum (Velloso) Verde (Haloragaceae).
- Authors: Oberholzer, I G , Mafokoane, D L , Hill, Martin P
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451555 , vital:75059 , https://hdl.handle.net/10520/EJC32727
- Description: Myriophyllum aquaticum (Velloso) Verde (Haloragaceae), parrot's feather, is a rooted aquatic plant, with stems of up to 3 m long and leafy terminal shoots. The plant roots in shallow water to form a dense tangle of stems and roots. The shoots emerge 200-500 mm above the water surface (Cilliers 1999). The leaves of the plant are feathery and occur in whorls. The stem-boring weevil, Listronotus marginicollis (Hustache) (Coleoptera: Curculionidae), was next considered as the most promising additional biological control agent for the control of M. aquaticum in southern Africa (Cilliers 1999).
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- Date Issued: 2007
The effect of temperature and salinity on oxygen consumption in the brachyuran crab Cyclograpsus punctatus (Crustacea: Decapoda: Grapsidae)
- Authors: Winch, James W W , Hodgson, Alan N
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447426 , vital:74624 , https://doi.org/10.1080/15627020.2007.11407384
- Description: The aquatic oxygen consumption of the estuarine brachyuran crab, Cyclograpsus punctatus, was investigated after a 24-hour acclimation period at different temperature (12.5, 20, 30°C) and salinity (9, 17.5, 35, and 44°) combinations . Salinity had no significant effect on oxygen consumption at 12.5 and 20°C in both large and small crabs. At 30°C and 44°, however, the rate of oxygen consumption declined in large crabs (from 0.233 to 0.176 mg O2 g wwt/h) and increased in small crabs (0.300 to 0.469 mg O2 g wwt/h). There was also a significant increase in the oxygen consumption (0.300 to 0.536 mg O2 g wwt/h) of small crabs at the high temperature/low salinity combination. Temperature had a significant effect on the rate of oxygen consumption at all salinities, with Q10 values ranging from 1.16 to 2.85. In all cases the mass-specific oxygen consumption rate of small crabs was higher than that of large crabs. The results suggest that the confinement of this species to the lower reaches of estuaries may, in part, be due to physiological constraints on juveniles and small individuals.
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- Date Issued: 2007
A Discussion Of Wireless Security Technologies
- Authors: Janse van Rensburg, Johanna , Irwin, Barry V W
- Date: 2006
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429852 , vital:72645 , https://www.researchgate.net/profile/Barry-Ir-win/publication/228864029_A_DISCUSSION_OF_WIRELESS_SECURITY_TECHNOLOGIES/links/53e9c5190cf28f342f41492b/A-DISCUSSION-OF-WIRELESS-SECURITY-TECHNOLOGIES.pdf
- Description: The 802.11 standard contains a number of problems, ranging from in-terference, co-existence issues, exposed terminal problems and regula-tions to security. Despite all of these it has become a widely deployed technology as an extension of companies’ networks to provide mobility. In this paper the focus will be on the security issues of 802.11. Several solutions for the deployment of 802.11 security exists today, ranging from WEP, WPA, VPN and 802.11 i, each providing a different level of security. These technologies contain pros and cons which need to be understood in order to implement an appropriate solution suited to a specific scenario.
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- Date Issued: 2006
Alternative media: a viable option for Southern Africa?
- Authors: Banda, Fackson
- Date: 2006
- Language: English
- Type: text , article
- Identifier: vital:6328 , http://hdl.handle.net/10962/d1008473 , https://core.ac.uk/download/pdf/145046852.pdf
- Description: preprint , The article attempts a historically and culturally based definition of alternative media. It then gives some case studies to illustrate the efficacy of such media forms, apart from highlighting the problems associated with them. It concludes that alternative media emerge to deal with specific ideological projects and, as such, must be viewed as satisfying a specific need at a specific point in time.
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- Date Issued: 2006
Ameliorating poverty in South Africa through natural resource commercialisation
- Authors: Shackleton, Sheona E
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6651 , http://hdl.handle.net/10962/d1007062
- Description: This short policy brief advocates for more attention to be paid to the potential of natural resource commercialisation as a means to livelihood security and poverty alleviation in rural South Africa. It is one of a set of four policy briefs based on the findings of several case studies across the country.
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- Date Issued: 2006
Cellulases (CMCases) and polyphenol oxidases from thermophilic Bacillus spp
- Authors: Mayende, Lungisa , Wilhelmi, Brendan S , Pletschke, Brett I
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6462 , http://hdl.handle.net/10962/d1005791 , http://dx.doi.org/10.1016/j.soilbio.2006.03.019
- Description: In composting, organic matter is degraded by cellulases and ligninolytic enzymes at temperatures typically above 50 °C. This study isolated thermophilic microorganisms from a compost system that were then screened for cellulase and polyphenol oxidase activity. Temperature optima for the cellulases and polyphenol oxidases were determined as 70 and 40 °C, respectively. Maximal cellulase activity was determined as 1.333 mg glucose released ml[superscript −1] min[superscript −1]. Maximal polyphenol oxidase activity attained was 5.111 nmol phenol ml[superscript −1] min[superscript −1]. Cellulases were found to be stable over a period of 1 h. The isolated compost microorganisms were identified as strains of Bacillus using 16S ribosomal DNA sequence analysis.
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- Date Issued: 2006
Re-estimation of erosion levels in Group I and II kimberlites between Lesotho, Kimberley and Victoria West, South Africa
- Authors: Hanson, E Kelsey , Moore, John M , Robey, Julian van Aardt , Bordy, Emese M , Marsh, Julian S
- Date: 2006
- Language: English
- Type: text , long abstracts
- Identifier: http://hdl.handle.net/10962/132144 , vital:36804
- Description: The estimation of post-emplacement kimberlite erosion in South Africa through the study of upper-crustal xenoliths is relatively unexplored; however the presence of these xenoliths has been recognized for well over a 100 years. Previously postemplacement erosion levels of a small number of kimberlite pipes have been inferred through the study of the degree of country-rock diagenesis, the depth of sill formation and the depth of the initiation of diatreme facies kimberlite.
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- Date Issued: 2006
Recruitment behaviour in the ponerine ant, Plectroctena mandibularis F. Smith (Hymenoptera: Formicidae)
- Authors: Wilkins, K J , Harman, K , Villet, Martin H
- Date: 2006
- Language: English
- Type: text , Article
- Identifier: vital:6887 , http://hdl.handle.net/10962/d1011647
- Description: Although workers of Plectroctena mandibularis laid trails with their stings while foraging, the trails appeared to be for individual orientation, because they never recruited nestmates to prey. However, both workers and queens laid trails when recruiting nestmates of either caste to new nest sites. During trail-laying, fluted hairs on the posterior edge of tergite VI were dragged along the ground, presumably applying a pheromone to the substrate. Anatomical and behavioural evidence suggests that pygidial gland secretions moved from the intersegmental pygidial gland between tergites VI and VII into a fingerprint-like, lamellar cuticular reservoir on the pygidium, and from there via the hairs to the substrate. These results suggest that recruitment may be crucial to moving nests but of value only to certain types of foraging, and that recruitment might even have originated in the Formicidae in the context of colony relocation, and then secondarily evolved to assist foraging.
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- Date Issued: 2006
The effect of water hyacinth, Eichhornia crassipes (Martius) SolmsLaubach (Pontederiaceae), on benthic biodiversity in two impoundments on the New Year's River, South Africa
- Authors: Midgley, John M , Hill, Martin P , Villet, Martin H
- Date: 2006
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442358 , vital:73978 , https://doi.org/10.2989/16085910609503868
- Description: Water hyacinth, Eichhornia crassipes (Martius) Solms-Laubach (Pontederiaceae), forms thick mats that affect water resource utilisation, but little is known about its impacts on biodiversity in aquatic ecosystems. The benthic invertebrate community and algal biomass were sampled under water hyacinth mats and in water hyacinth-free water over a 13-month period, using artificial substrates in New Year's Dam, Eastern Cape Province, South Africa. The number of families per substrate (U = 796.5, P 0.001), number of individuals per substrate (U = 620.5, P 0.001), Shannon-Weiner Diversity Index (U = 1 038, P 0.001), Margalef's Richness index (U = 1 136, P 0.002), Pielou's Evenness Index (U = 1 230, P 0.001) and chlorophyll a (U = 678, P 0.01) were all significantly lower under water hyacinth mats than in water hyacinth-free zones. Similarly, multivariate analyses showed more diversity in invertebrate communities in open water than under water hyacinth. Thus, the control of water hyacinth is important, in order to prevent both ecological and economic impacts of biodiversity loss.
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- Date Issued: 2006
The emplacement of class 1 kimberlites: part 1, evidence of geological features
- Authors: Skinner, E M W , Marsh, Julian S
- Date: 2006
- Language: English
- Type: text , Long abstract
- Identifier: http://hdl.handle.net/10962/132729 , vital:36877
- Description: This paper has been prepared specifically for the September 2006, Kimberlite Emplacement Workshop, Saskatoon, Canada. To this end, emphasis is placed on a big bang/ bottom-up model for the emplacement of Class 1 kimbertite pipes first presented by Clement and Reid (1989) and reinforced by Skinner and Marsh (2004). In this part (Part 1) the evidence of various geological features is presented.
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- Date Issued: 2006
The emplacement of class 1 kimberlites: part 2, petrographic evidence
- Authors: Skinner, E M W , Marsh, Julian S
- Date: 2006
- Language: English
- Type: text , Long abstract
- Identifier: http://hdl.handle.net/10962/132740 , vital:36878
- Description: This paper has been prepared specifically for the September 2006, Kimberlite Emplacement Workshop, Saskatoon, Canada. To this end, emphasis is placed on a big bang/ bottom-up model for the emplacement of Class 1 kimberlite pipes first presented by Clement and Reid (1989) and reinforced by Skinner and Marsh (2004). In this part (Part 2) petrographic evidence is presented in support of evidence provided by the synthesis of specific geological features as presented in Part 1.
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- Date Issued: 2006
Trophic importance of kelp-derived suspended particulate matter in a through-flow sub-Antarctic system
- Authors: Kaehler, Sven , Pakhomov, Evgeny A , Kalin, R M , Davis, S
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6876 , http://hdl.handle.net/10962/d1011624
- Description: Spatial dynamics of surface chlorophyll concentrations, diatom abundance and carbon and nitrogen stable isotope signatures of surface suspended particulate matter (SPM) were investigated during a bloom event observed in March 2003 in the vicinity of the sub-Antarctic Prince Edward Islands. The surface water composition was studied to estimate the overall importance and spatial extent of kelp derived SPM in the water column of the islands. It was observed that high chlorophyll concentrations (up to 2 mg m–3) between and downstream of the islands could not be explained by the development of the diatom bloom. Instead, microscopic and stable isotope analyses suggested that the chlorophyll signal was largely derived from the residual chlorophyll in fresh and decaying particles of small fragments of the kelp Macrocystis laevis, an endemic kelp species abundant along the shoreline of the islands. The findings of this study suggest that the dietary subsidy of kelp-derived carbon and nitrogen to benthic communities and possibly the plankton is not limited to the vicinity of kelp beds, but rather is a widespread phenomenon between the islands. Due to the dominating unidirectional Antarctic Circumpolar Current, large quantities of kelp-derived SPM may be transported and utilised tens of kilometres downstream of the islands.
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- Date Issued: 2006
A.k.a. Breyten Breytenbach : critical approaches to his writings and paintings, J.L. Coullie and J.U. Jacobs, eds. : book review
- Authors: Vorster, Anton F
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6335 , http://hdl.handle.net/10962/d1012399
- Description: a.k.a. Breyten Breytenbach brings together a collection of 14 essays by 12 scholars on the work of this remarkable South African writer, poet and painter. Designating Breytenbach as ‘South African’ is, of course, already a highly contentious act. It relates directly to the central concern of this volume (and one of the central concerns of Breytenbach’s work), namely the question of identity. The title characterises the artist’s proper name as but one in a series of constantly shifting and interchanging personas adopted in his art (and in his life, e.g. when working underground in the 1970s to contribute to the overthrow of the apartheid regime). The painting on the cover further explores the theme of the mask, with the white male figure’s face covered by a book-like object (although his eyes are partially visible through the object), and the presence of a burning hat floating in the air next to him serves as an additional link with many of his other paintings where headgear is associated with shifting identities, as pointed out by Marilet Sienaert in her essay, “The I of the Beholder: Identity and Place in the Art and Writing.” Like several of the other authors, Sienaert places great emphasis on the notion of movement or transformation as critical to Breytenbach’s thinking and creative practice. It is virtually unavoidable, given his background, that he should grapple with “the contemporary notion of ‘home’ being both everywhere and nowhere”, and that travel and nomadism should have become two of the most prominent themes in his poetry as well as his prose. Identity and creativity are both dependent upon the ability to constantly renew oneself and to “keep moving”.
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- Date Issued: 2005
African herbal medicines in the treatment of HIV: Hypoxis and Sutherlandia: an overview of evidence and pharmacology
- Authors: Mills, Edward , Cooper, Curtis , Seely, Dugald , Kanfer, Isadore
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6401 , http://hdl.handle.net/10962/d1006337
- Description: In Africa, herbal medicines are often used as primary treatment for HIV/AIDS and for HIV-related problems. In general, traditional medicines are not well researched, and are poorly regulated. We review the evidence and safety concerns related to the use of two specific African herbals, which are currently recommended by the Ministry of Health in South Africa and member states for use in HIV: African Potato and Sutherlandia. We review the pharmacology, toxicology and pharmacokinetics of these herbal medicines. Despite the popularity of their use and the support of Ministries of Health and NGOs in some African countries, no clinical trials of efficacy exist, and low-level evidence of harm identifies the potential for drug interactions with antiretroviral drugs. Efforts should be made by mainstream health professionals to provide validated information to traditional healers and patients on the judicious use of herbal remedies. This may reduce harm through failed expectations, pharmacologic adverse events including possible drug/herb interactions and unnecessary added therapeutic costs. Efforts should also be directed at evaluating the possible benefits of natural products in HIV/AIDS treatment.
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- Date Issued: 2005
Biological removal of nitrogen species from metal-processing wastewater
- Authors: Kasia, J M , Duncan, John R , Burgess, Jo E
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6482 , http://hdl.handle.net/10962/d1006256
- Description: Although several nitrification/denitrification processes are established for the removal of ammonia and nitrate from municipal and industrial wastewaters, there are few reported results on the removal of these ions from metal-processing and finishing wastewaters. Unlike municipal wastewater, there is very little organic content in metal-processing wastewaters. Sources of ammonia and nitrate in the wastewater include the use of ammonium-nitrate-fuel oil as a blasting agent, and the use of other nitrogen-containing reagents during processing. The objective of this work was to investigate a biological process for the removal of nitrogenous compounds from real metal-processing wastewater. The system comprised an aerobic continuously stirred tank reactor (CSTR) followed by an anaerobic packed column and was run using real wastewater from a metal-processing operation. The system was inoculated using humus sludge from a municipal trickling filter and a period of approximately four weeks was required for a denitrifying biofilm to develop. Results showed that ammonia removal occurred readily in the CSTR while nitrite oxidation was slower to develop. The CSTR was found to be suitable for ammonia oxidation; up to 89% ammonia removal was achieved. By employing an integrated process comprising nitrification and denitrification, high ammonia removal efficiencies can be obtained. An effluent that is low in ammonia can be obtained with this system with additional carbon introduced after the CSTR. The gravel-packed column reactor was found to be unsuitable for the removal of nitrate in the configuration used (maximum 15% removal efficiency). The critical parameters for denitrification are nitrate concentration, temperature, influent flow rate and mean cell retention time. Nitrate removal did not meet the expectations projected by previous authors' work using synthetic wastewater.
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- Date Issued: 2005
Fire behaviour in a semi-arid Baikiaea plurijuga savanna woodland on Kalahari sands in western Zimbabwe
- Authors: Gambiza, James , Campbell, Bruce M , Moe, Stein R
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6630 , http://hdl.handle.net/10962/d1006822
- Description: Human-induced fires are a major disturbance in Baikiaea plurijuga woodland savannas that are economically important for timber production. Most fires occur during the late dry season, when they may severely damage woody plants. Prescribed burning during the early dry season is a management strategy to reduce fuel loads and thus the incidence of intense fires during the late dry season. There is, however, little information on fire behaviour characteristics of early dry season fires.We studied the relationship between experimental fuel conditions and fire behaviour by lighting 15 fires during the early dry season in a Baikiaea woodland. Fire intensity ranged from 25 to 1341 kW m[superscript (-1)], while rate of spread of fire varied between 0.01 and 0.35ms[superscript (-1)]. Fire intensity and rate of spread were positively related to flame height, leaf-scorch height and proportion of the area burnt. The relationships suggest that fire characteristics can be retrospectively determined using a variable such as scorch height. The grass fuel load, wind speed, relative humidity and to a lesser extent fuel moisture were important predictors of rate of spread, flame height, leaf-scorch height and proportion of the area burnt, with no impact due to the litter fuel load. The grass fuel load and wind speed had a positive effect on rate of spread, whereas relative humidity and fuel moisture had a negative effect. These findings indicate that managers can predict the likely damage to woody plants during an early dry season burn by assessing the grass fuel load and weather conditions at the time of burning.
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- Date Issued: 2005
Reflections on the ‘3rd World Environmental Education Congress: Educational pathways towards sustainability’, Italy, 2005
- Authors: Lotz-Sisitka, Heila
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6096 , http://hdl.handle.net/10962/d1008619
- Description: Conference Theme: The congress theme ‘Educational pathways towards sustainability’ foregrounded the current ‘state of play’ in environmental education / education for sustainability, at the start of the UN Decade of Education for Sustainable Development (DESD), and drew attention to the role of education in creating pathways towards sustainability. Mario Solomone, convenor of the congress, in his orientation to the congress describes the congress as being about ‘cultural changes and cultural forces for change’, highlighting the role of education, training and communication in redirecting values, knowledge and behaviour to construct a human society ‘that is fairer and more aware of the equilibrium of a beautiful and fragile planet’ (Salomone, 2005: 6). To facilitate deliberations during the conference a set of interrelated themes were established which included: communication and the environment; paths to sustainability; research and assessment in environmental education; sustainable education; training the trainers; community awareness; promoting participation and governance and creating a network; economics and ecology; environment and health; farming and related issues; ethics; and emotional involvements. These congress themes, together with an impressive array of keynote papers kept congress participants actively engaged with the question of the DESD.
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- Date Issued: 2005
Situated culture, ethics and new learning theory: emerging perspectives in environmental education research
- Authors: Lotz-Sisitka, Heila
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6095 , http://hdl.handle.net/10962/d1008617
- Description: Celebrating the 8th International Invitational Research and Development Seminar. This edition of the EEASA Journal celebrates the hosting of the 8th International Invitational Research and Development Seminar on Environmental and Health Education in South Africa in March 2005. The International Invitational Research and Development Seminars are ‘special events’ in the field of environmental and health education research. They are characterised by their democratic, deliberative nature, and by their intent to scope innovation and methodological issues. First established some years ago in Copenhagen, Denmark, these seminars have provided an evolving international forum for researchers interested in research methodology to meet and frame new themes, trends and issues arising in the field of environmental education and health education research.
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- Date Issued: 2005