A Digital Forensic investigative model for business organisations
- Authors: Forrester, Jock , Irwin, Barry V W
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430078 , vital:72664 , https://www.researchgate.net/profile/Barry-Ir-win/publication/228783555_A_Digital_Forensic_investigative_model_for_business_organisations/links/53e9c5e80cf28f342f414987/A-Digital-Forensic-investigative-model-for-business-organisations.pdf
- Description: When a digital incident occurs there are generally three courses of ac-tions that are taken, generally dependant on the type of organisation within which the incident occurs, or which is responding the event. In the case of law enforcement the priority is to secure the crime scene, followed by the identification of evidentiary sources which should be dispatched to a specialist laboratory for analysis. In the case of an inci-dent military (or similar critical infrastructures) infrastructure the primary goal becomes one of risk identification and elimination, followed by re-covery and possible offensive measures. Where financial impact is caused by an incident, and revenue earning potential is adversely af-fected, as in the case of most commercial organisations), root cause analysis, and system remediation is of primary concern, with in-depth analysis of the how and why left until systems have been restored.
- Full Text:
- Date Issued: 2007
A geopolitical analysis of long term internet network telescope traffic
- Authors: Irwin, Barry V W , Pilkington, Nik , Barnett, Richard J , Friedman, Blake
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428142 , vital:72489 , https://www.researchgate.net/profile/Barry-Ir-win/publication/228848896_A_geopolitical_analysis_of_long_term_internet_network_telescope_traffic/links/53e9c5190cf2fb1b9b672aee/A-geopolitical-analysis-of-long-term-internet-network-telescope-traffic.pdf
- Description: This paper presents results form the analysis of twelve months of net-work telescope traffic spanning 2005 and 2006, and details some of the tools developed. The most significant results of the analysis are high-lighted. In particular the bulk of traffic analysed had its source in the China from a volume perspective, but Eastern United States, and North Western Europe were shown to be primary sources when the number of unique hosts were considered. Traffic from African states (South Af-rica in particular) was also found to be surprisingly high. This unex-pected result may be due to the network locality preference of many automated agents. Both statistical and graphical analysis are present-ed. It is found that a country with a high penetration of broadband con-nectivity is likley to feature highly in Network telescope traffic, as are networks logically close to the telescope network.
- Full Text:
- Date Issued: 2007
An analysis of the influence of question design on learners' approaches to number pattern generalisation tasks:
- Authors: Samson, Duncan , Schäfer, Marc
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141026 , vital:37938 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC20890
- Description: This paper reports on a study of the extent to which question design affects the solution strategies adopted by children when solving linear number pattern generalisation tasks presented in pictorial and numeric contexts. The research tool comprised a series of 22 pencil-and-paper exercises based on linear generalisation tasks set in both numeric and two-dimensional pictorial contexts. The responses to these linear generalisation questions were classified by means of stage descriptors as well as stage modifiers. The method or strategy adopted was analysed and classified into one of seven categories. In addition, a meta-analysis focused on the formula derived for the nth term in conjunction with its justification. The results of this study strongly support the notion that question design can play a critical role in influencing learners' choice of strategy and level of attainment when solving pattern generalisation tasks. An understanding of the importance of appropriate question design has direct pedagogical application within the context of the mathematics classroom.
- Full Text:
- Date Issued: 2007
An ontology-based, multi-modal platform for the inclusion of marginalized rural communities into the knowledge society
- Authors: Thinyane, Mamello , Dalvit, Lorenzo , Slay, Hannah , Mapi, Thandeka , Terzoli, Alfredo
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431218 , vital:72755 , https://doi.org/10.1145/1292491.1292508
- Description: With the information revolution that promises to shape the 21st century, knowledge has become the prime commodity, very much like land, means of production and capital have been at different times in the past. Access to information, made instantly available by the growth of the Internet, determines access to economic resources, social participa-tion and better quality of life. For this reason, the knowledge stored on the Web and the advantages offered by the spread of Information and Communication Technology (ICT) are equally important for rich socie-ties to prosper and for poor ones to develop. The only difference is that marginalised communities do not have access to the tools and have little control over the content found in the domain of ICTs. In this paper we describe an intervention to develop the potential of a typical rural community in South Africa through ICTs. This involves providing Inter-net connectivity and deploying a platform to support e-commerce, e-learning, e-government and e-health. The core of the platform is an on-tology-based model designed to integrate and respond to Indigenous Knowledge Systems. This has been achieved by combining a deep understanding of local knowledge and social networks with the use of authoring, communication and ontology-management tools. The prima-ry goal of this new approach is to find a way to make ICT solutions more sensitive to the local context, and therefore more effective. Sec-ondly, we hope to foster a sense of ownership of the project among the community, by capitalising on local knowledge and resources.
- Full Text:
- Date Issued: 2007
An XML-Based Approach to Audio Connection Management
- Authors: Foss, Richard , Klinkradt, Bradley
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427253 , vital:72425 , https://www.aes.org/e-lib/browse.cfm?elib=14115
- Description: An XML-based approach to firewire audio connection management has been developed that allows for the creation of connection management applications using a range of implementation tools. The XML connection management requests flow between a client and server, where the client and server can reside on the same or separate workstations. The server maintains the state of the firewire audio device configuration as well as information about potential users. XML is also used to control user access and booking of devices.
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- Date Issued: 2007
Anaerobic digestion of fungally pre-treated wine distillery wastewater
- Authors: Melamane, Xolisa L , Tandlich, Roman , Burgess, Jo E
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71740 , vital:29932 , https://doi.org/10.5897/AJB2007.000-2305
- Description: The combination of fungal pre-treatment with Trametes pubescens and anaerobic digestion were tested for the removal of chemical oxygen demand (COD) and phenolic compounds from wine distillery wastewater. The COD removal efficiency after fungal pre-treatment reached 53.3%. During digestion, pH buffering was achieved using CaCO3 and K2HPO4. This provided a stable environment inside digester for efficient and time-independent COD removal. The total COD removal efficiency reached 99.5%, and the system proved able to eliminate shock COD loads, as indicated by the concentrations of sludge and volatile fatty acids. Complex changes of phenolic compounds are suspected in anaerobic digestion system, and are investigated further.
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- Date Issued: 2007
Antjie Krog and the accumulation of ‘media meta‐capital’:
- Authors: Garman, Anthea
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159713 , vital:40336 , DOI: 10.1080/1013929X.2007.9678272
- Description: While Krog's significant body of work in poetry, prose and journalism is undoubtedly central in her trajectory towards international renown, in this essay I explore the dynamics of her “meteoric rise in status”. The news media's role in mediating Krog to the world for nearly 40 years becomes crucial to this investigation. I use a mix of media theory and field theory to illuminate the multi‐faceted and complex relationship Krog has had with the news media and I argue that her acquisition of ‘media meta‐capital’ has played a significant role in her attainment of a unique voice and speaking platform in a postapartheid, public domain in which few white voices, and especially Afrikaner ones, are being heard.
- Full Text:
- Date Issued: 2007
Assessing the effects of invasive alien species on rural livelihoods: Case examples and a framework from South Africa
- Authors: Shackleton, Charlie M , McGarry, Dylan K , Fourie, Saskia , Gambiza, James , Shackleton, Sheona E , Fabricius, Christo
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181279 , vital:43715 , xlink:href="https://doi.org/10.1007/s10745-006-9095-0"
- Description: The detrimental impacts of invasive alien species (IAS) on ecosystem goods and services and local and regional economies are well documented. However, the use of IAS by rural communities is little understood, and rarely factored into IAS control programmes. Understanding the use of IAS by rural communities and factoring these into cost-benefit models is complex, depending upon a range of local-level attributes such as the time since invasion, abundance, and local-level costs and benefits. This paper reports on two case studies examining the role of IAS in rural livelihoods in the Eastern Cape, South Africa. In both cases, rural communities made widespread consumptive use of the IAS and generally would prefer higher densities, except in certain key localities. Several households traded in IAS products to generate supplementary income. We present a conceptual framework to guide interpretation of these and future case studies, considering attributes such as time since invasion, the competitiveness of the species, and the relative costs and benefits.
- Full Text:
- Date Issued: 2007
Bridging the gap for Next Generation Services: Presence Services on Legacy Devices
- Authors: Moyo, Thamsanqa , Thinyane, Mamello , Wright, Madeleine , Irwin, Barry V W , Clayton, Peter G , Terzoli, Alfredo
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428177 , vital:72491 , https://d1wqtxts1xzle7.cloudfront.net/49665432/Paper_2063_20-_20Moyo-libre.pdf?1476717366=andresponse-content-disposi-tion=inline%3B+filename%3DBridging_the_gap_for_Next_Generation_Ser.pdfandEx-pires=1714737455andSignature=RRbr9pzIYSYX8v7FG6FzV4tu3dFXm9qmmqq5WirOhuYdt--mjOfcDHQNLPYZHCmtgYZWdVk6bVFxfGOVJxgXrvkTe2QN2AZV3XfFTZ3mi1s3A5gw2jIXOVHrYUnaf~POgdijdY85mqWhco3vL6Qk3sOZgYjIlTF5ZGAKg1S54W978Nom01cT2~oqRA0Et6mTNmydWfF5MhFxQIq~LNmYqEqmEESKkkWQFwg6xJJUu0uGffbaZXXBA6oDI2cpfkz1FleKyKaRDRJvdfnuTHPoJJ4TzfO6DDVCWKvJ45jaxIzaGmK-03Ai29I-DPyy-c557kZh~kF3rmDg3zrXVNaL8A__andKey-Pair-Id=APKAJLOHF5GGSLRBV4ZA
- Description: Next generation services are provided by applications that leverage packet-based domains. A challenge faced by such services is the support for multiple devices, including legacy devices. Our paper examines a strategy for the pro-vision of next generation services on legacy cellular network devices. We ad-vocate that the provision of next generation services via applications on the SIM card allows for the deployment of such services on legacy devices. We demonstrate this assertion through a proof of concept application, SIMPre, that resides on a SIM card. SIMPre implements a presence service by leveraging Java Card, the SIM Application Toolkit and the OMA IMPS standard. We show that it is possible to provide a next generation service on the SIM card such that it ubiquitously integrates with the functionality of a legacy device. We con-clude through this demonstration that the SIM card is a viable option for provid-ing backward compatibility to legacy devices in the implementation of next generation services.
- Full Text:
- Date Issued: 2007
Bridging the gap for Next Generation Services: Presence Services on Legacy Devices
- Authors: Moyo, Thamsanqa , Thinyane, Mamello , Wright, Madeleine , Irwin, Barry V W , Clayton, Peter G , Terzoli, Alfredo
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428176 , vital:72492 , https://d1wqtxts1xzle7.cloudfront.net/49665432/Paper_2063_20-_20Moyo-libre.pdf?1476717366=andresponse-content-disposi-tion=inline%3B+filename%3DBridging_the_gap_for_Next_Generation_Ser.pdfandEx-pires=1714737455andSignature=RRbr9pzIYSYX8v7FG6FzV4tu3dFXm9qmmqq5WirOhuYdt--mjOfcDHQNLPYZHCmtgYZWdVk6bVFxfGOVJxgXrvkTe2QN2AZV3XfFTZ3mi1s3A5gw2jIXOVHrYUnaf~POgdijdY85mqWhco3vL6Qk3sOZgYjIlTF5ZGAKg1S54W978Nom01cT2~oqRA0Et6mTNmydWfF5MhFxQIq~LNmYqEqmEESKkkWQFwg6xJJUu0uGffbaZXXBA6oDI2cpfkz1FleKyKaRDRJvdfnuTHPoJJ4TzfO6DDVCWKvJ45jaxIzaGmK-03Ai29I-DPyy-c557kZh~kF3rmDg3zrXVNaL8A__andKey-Pair-Id=APKAJLOHF5GGSLRBV4ZA
- Description: Next generation services are provided by applications that leverage packet-based domains. A challenge faced by such services is the support for multiple devices, including legacy devices. Our paper examines a strategy for the pro-vision of next generation services on legacy cellular network devices. We ad-vocate that the provision of next generation services via applications on the SIM card allows for the deployment of such services on legacy devices. We demonstrate this assertion through a proof of concept application, SIMPre, that resides on a SIM card. SIMPre implements a presence service by leveraging Java Card, the SIM Application Toolkit and the OMA IMPS standard. We show that it is possible to provide a next generation service on the SIM card such that it ubiquitously integrates with the functionality of a legacy device. We con-clude through this demonstration that the SIM card is a viable option for provid-ing backward compatibility to legacy devices in the implementation of next generation services.
- Full Text:
- Date Issued: 2007
Bycatch and discarding in the South African demersal trawl fishery
- Authors: Walmsley, Sarah A , Leslie, Rob W , Sauer, Warwick H H
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123944 , vital:35518 , https://doi.10.1016/j.fishres.2007.03.002
- Description: Observers aboard commercial trawlers collected data on the total catch composition of 614 and 479 hauls made by vessels operating off the south and west coasts of South Africa, respectively. On the south coast, four fishing areas were identified on the basis of target species and fishing depth. On the west coast, hauls were separated into those targeting hake Merluccius spp. in four depth ranges (0–300, 301–400, 401–500, and >500 m) and those targeting monkfish Lophius vomerinus. For each area, the catch composition was calculated and the species assemblages were investigated using cluster analysis and multi-dimensional scaling. Finally, for each coast, the weight of fish discarded annually was estimated. On the south coast, although hake dominated, between 21% and 47% of the catch was not hake, depending on the fishing area. In comparison, hake dominated west coast catches, the proportion of hake increasing with depth. For each fishery investigated, approximately 90% of the catch was processed and landed. However, estimates of annual discards indicate that the south and west coast fisheries may annually discard 9000 or 10,000 t and 17,000 or 25,000 t, of undersized and unutilizable fish and offal, respectively, depending on the estimation method used. When developing strategies to limit or enhance utilization of bycatch, cognisance should be taken of the differences in catch composition between the south and west coasts and of the importance of bycatch revenue to south coast fishing companies.
- Full Text:
- Date Issued: 2007
Characterization of self-assembled monolayers of iron and cobalt octaalkylthiosubstituted phthalocyanines and their use in nitrite electrocatalytic oxidation
- Authors: Matemadombo, Fungisai , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/271182 , vital:54519 , xlink:href="https://doi.org/10.1016/j.electacta.2007.05.002"
- Description: Cobalt and iron phenylthiosubstituted phthalocyanines have been deposited on Au electrode surfaces through the self-assembled monolayer (SAM) technique. The so formed layers were studied using voltammetric and impedance techniques. These SAMs blocked a number of Faradic processes and electrocatalyzed the oxidation of nitrite. The electrocatalytic parameters of the cobalt and iron phenylthiosubstituted phthalocyanines deposited on Au electrodes in nitrite solution were studied. Nitrite overpotentials which are lower than ever reported were obtained in this work for the iron phenylthiosubstituted phthalocyanines with very high stability.
- Full Text:
- Date Issued: 2007
Cobalt Phthalocyanine Molecular Electrode for the Electrochemical Investigation of the Release of Glutathione upon Copper-Catalyzed Decomposition of S-Nitrosoglutathione
- Authors: Sehlotho, Nthapo , Griveau, Sophie , Nyokong, Tebello , Bedioui, Fethi
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281201 , vital:55701 , xlink:href="https://doi.org/10.1002/elan.200603656"
- Description: Decomposition of S-nitrosoglutathione (GSNO) in phosphate buffer solution at physiological pH 7.4 in the presence of cuprous ion as a catalyst and sodium borohydride as a reducing agent is analyzed by observing the transient apparition of reduced glutathione GSH through its electrooxidation. Transient formation of GSH, upon decomposition of 1 mM GSNO in presence of 0.025 mM Cu(NO3)2 and 1 mM NaBH4 was detected by using an ordinary pyrolytic graphite electrode modified with an adsorbed monolayer of cobalt phthalocyanine at 0 V vs. SCE.
- Full Text:
- Date Issued: 2007
Comparative electrooxidation of nitrite by electrodeposited Co (II), Fe (II) and Mn (III) tetrakis (benzylmercapto) and tetrakis (dodecylmercapto) phthalocyanines on gold electrodes
- Authors: Agboola, Bolade , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281212 , vital:55702 , xlink:href="https://doi.org/10.1016/j.aca.2007.01.031"
- Description: This work reports on the electrooxidation of nitrite using Co(II), Fe(II) and Mn(III) tetrakis (benzylmercapto) and tetrakis (dodecylmercapto) phthalocyanines electrodeposited onto a gold electrode. Good catalytic activity (in terms of lowering overpotential) was obtained for these molecules when compared to previously reported MPc catalysts. The catalytic current was found to vary linearly with nitrite concentration in the range employed in this work (0.1–1 mM) and high sensitivities ranging from 6.9 to 9.9 μA mM−1 were observed for all the modified electrodes.
- Full Text:
- Date Issued: 2007
Comparative electrooxidation of sulphite by self-assembled monolayers (SAMs) of Co (II), Fe (II), Ni (II) and Mn (III) tetrakis benzylmercapto and dodecylmercapto metallophthalocyanines complexes on gold electrodes
- Authors: Agboola, Bolade , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281223 , vital:55703 , xlink:href="https://doi.org/10.1016/j.talanta.2006.11.042"
- Description: This work reports on the use of Co(II), Fe(II), Mn(III) and Ni(II) tetrakis benzylmercapto and dodecylmercapto phthalocyanine complexes for gold electrode modification for electrooxidation of sulphite ions. The complexes were successfully used to modify gold electrodes by self-assembled monolayer (SAM) technique. The self-assembled films are stable and showed blocking characteristics towards the following Faradaic processes; gold surface oxidation, underpotential deposition (UPD) of copper and solution redox chemistry of [Fe(H2O)63+]/[Fe(H2O)62+]. All the modified electrodes showed improved catalytic activities than the unmodified gold electrode towards sulphite ion electrooxidation with all the modified electrodes exhibiting high resistance to electrode surface passivation. Better catalytic performance were obtained for the CoPcs, FePcs and MnPcs which have metal based redox processes within the range of the sulphite electrooxidation peak, while the NiPcs which did not show metal based redox reaction performed less. The catalytic current was found to be linear with sulphite ion concentration in the concentration range employed in this work (0.1–1 mM) and sensitivities ranging from 1.68 to 2.96 μA/mM were observed for all the modified electrodes. Mechanisms of the catalytic oxidation of sulphite ions are proposed.
- Full Text:
- Date Issued: 2007
Comparative photocatalytic efficiency of oxotitanium (IV) phthalocyanines for the oxidation of 1-hexene
- Authors: Tau, Prudence , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/271193 , vital:54520 , xlink:href="https://doi.org/10.1016/j.molcata.2007.04.005"
- Description: The comparative photocatalytic activities of aryloxy and arylthio tetrasubstituted oxotitanium(IV) phthalocyanine complexes for the oxidation of 1-hexene in DCM are reported for the first time. The singlet oxygen quantum yield, photostability and photocatalytic properties are investigated. The catalysts effectively catalyse 1-hexene to 1,2-epoxyhexane and 1-hexen-3-ol as major and minor products respectively. The photooxidation products are formed via two reaction mechanisms, namely via singlet oxygen (Type II) and radical (Type I) reaction pathways. These are also dependent on the singlet oxygen quantum yields and photostabilities of the phthalocyanines. Complex 1a that is peripherally substituted with phenoxy groups exhibited the best activity in terms of overall performance.
- Full Text:
- Date Issued: 2007
Critical assessment of the quartz crystal microbalance with dissipation as an analytical tool for biosensor development and fundamental studies
- Authors: Fogel, Ronen , Mashazi, Philani N , Nyokong, Tebello , Limson, Janice L
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/271204 , vital:54521 , xlink:href="https://doi.org/10.1016/j.bios.2007.03.012"
- Description: One of the challenges in electrochemical biosensor design is gaining a fundamental knowledge of the processes underlying immobilisation of the molecules onto the electrode surface. This is of particular importance in biocomposite sensors where concerns have arisen as to the nature of the interaction between the biological and synthetic molecules immobilised. We examined the use of the Quartz Crystal Microbalance with Dissipation (QCM-D) as a tool for fundamental analyses of a model sensor constructed by the immobilisation of cobalt(II) phthalocyanine (TCACoPc) and glucose oxidase (GOx) onto a gold-quartz electrode (electrode surface) for the enhanced detection of glucose. The model sensor was constructed in aqueous phase and covalently linked the gold surface to the TCACoPc, and the TCACoPc to the GOx, using the QCM-D. The aqueous metallophthalocyanine (MPc) formed a multi-layer over the surface of the electrode, which could be removed to leave a monolayer with a mass loading that compared favourably to the theoretical value expected. Analysis of frequency and dissipation plots indicated covalent attachment of glucose oxidase onto the metallophthalocyanine layer. The amount of GOx bound using the model system compared favourably to calculations derived from the maximal amperometric functioning of the electrochemical sensor (examined in previously-published literature, Mashazi, P.N., Ozoemena, K.I., Nyokong, T., 2006. Electrochim. Acta 52, 177–186), but not to theoretical values derived from dimensions of GOx as established by crystallography. The strength of the binding of the GOx film with the TCACoPc layer was tested by using 2% SDS as a denaturant/surfactant, and the GOx film was not found to be significantly affected by exposure to this. This paper thus showed that QCM-D can be used in order to model essential processes and interactions that dictate the functional parameters of a biosensor.
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- Date Issued: 2007
Determining the daily spawning cycle of the chokka squid, Loligo reynaudii off the South African Coast
- Authors: Melo, Y , Sauer, Warwick H H
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124275 , vital:35588 , https://doi.10.1007/s11160-006-9034-6
- Description: The study investigated the duration and peak of the daily spawning cycle of the chokka squid Loligo reynaudii, and the possibility of estimating the spawning frequency by means of classification and grouping (by age) of postovulatory follicles. Post-ovulatory follicles were classified into three types: new, intermediate or old, based in part on the degree of resorption of the follicles determined from histological sections. Ovulation in this species appears to be a rapid process, seen by the occurrence of both mature oocytes and post-ovulatory follicles in partially spent ovaries. Results suggest that chokka squid present a diel timing of spawning, with successive periods of egg accumulation at night, interrupted by periods of active spawning during the day. The ovarian cycle for this species appears typical of serial spawners. During the spawning phase ovaries go through ripe, partially spent and recovering stages by undergoing a process of maturation, ovulation and redeveloping, where a new batch of advanced oocytes is recruited. The cycle typically appears to last between 24 and 36 h, and may depend on a number of factors such as environmental conditions and the presence of predators. The short-lived (about 14 h) nature of the post-ovulatory follicles precludes the calculation of the exact spawning interval and does not allow us to accurately predict the spawning frequency. Together with the degree of oviduct fullness they do however give a good indication of imminent or recent spawning.
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- Date Issued: 2007
Direct-use values of non-timber forest products from two areas on the Transkei Wild Coast
- Authors: Shackleton, Charlie M , Timmermans, Herman G , Nongwe, N , Hamer, Nicholas G , Palmer, N R
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181268 , vital:43714 , xlink:href="https://doi.org/10.1080/03031853.2007.9523764"
- Description: It is now widely appreciated internationally that rural communities make extensive use of wild resources, and that this use has significant direct use value. The number of case studies in South Africa that have valued the use of such resources are small, albeit growing. Yet none of them have been from coastal sites, which would include use of marine resources, nor have previous studies included the non-biological resources of sand and clay for building purposes. This paper addresses this gap, through examination of the role and value of wild resources in rural livelihoods of households in the Ntubeni and Cwebe areas of the Transkei Wild Coast in the Eastern Cape. Households used a wide range of resources collected from the surrounding communal lands and the Dwesa Cwebe Nature Reserve. Major differences between the sites were the widespread use of bushmeat, shellfish and building sand at Ntubeni compared with relatively small use of these three resources at Cwebe. These differences resulted in a markedly higher, gross, annual, direct-use value at Ntubeni than at Cwebe. The gross, annual, direct-use value averaged across all resources (excluding medicinal plants) and all households (user and non-users) was over R12 000 at Ntubeni, compared to R4 858 at Cwebe. At Ntubeni over half of the total annual direct-use value was contributed by fish and shellfish, indicating the need for more studies in coastal areas. A similar pattern was not evident at Cwebe, because residents did not have access to a rocky shoreline outside of the marine reserve. Local trade was highly variable, both between resources and between households. Averaging the value of trade across all households (i.e. traders and non-traders), gave a total gross, annual value of R1 660 and R600 at Ntubeni and Cwebe, respectively.
- Full Text:
- Date Issued: 2007
Does 'African mathematics' facilitate access to mathematics?: towards an ongoing critical analysis of ethnomathematics in a South African context
- Authors: Horsthemke, Kai , Schäfer, Marc
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141004 , vital:37936 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC20885
- Description: Mosibudi Mangena, the Minister of Science and Technology, said in an address to the Annual Congress of the South African Mathematical Society at the University of the Potchefstroom, November 2, 2004: "There is one thing we need to address before anything else. We need to increase the number of young people, particularly blacks and women, who are able to successfully complete the first course in Mathematics at our universities." How is this to be achieved? A popular trend involves a call for the introduction and incorporation of so-called ethnomathematics, and more particularly 'African mathematics', into secondary and tertiary curricula. Although acknowledging the obvious benefits of so-called ethnomathematics, this paper critically analyses three aspects of ethnomathematics that have been neglected in past critiques. Our focus is not on the relationship as such between ethnomathematics and mathematics education. Our critique involves (1) epistemological and logical misgivings, (2) a new look at practices and skills, (3) concerns about embracing 'African mathematics' as valid and valuable - just because it is African.
- Full Text:
- Date Issued: 2007