Dancing around the same spot? land reform and Ngos in Zimbabwe: the case of SOS Children’s Villages
- Authors: Helliker, Kirk D
- Date: 2009
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/61006 , vital:27910 , http://dx.doi.org/10.4314/asr.v13i2.60408
- Description: This paper discusses the rural-based operations of an international NGO in Mashonaland Central province, Zimbabwe. The aim is to highlight the contingent variation of NGO practices within defined limits. It does this through 'thick description’ of the NGO of focus, the SOS Children’s Village, and compares its 'handling' of the transforming countryside with the response of two other NGOs. It concludes by suggesting some conceptual points in understanding organizational dispositions of NGOs.
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Data quality in thermal summation development models for forensically important blowflies
- Authors: Richards, Cameron S , Villet, Martin H
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441889 , vital:73932 , https://doi.org/10.1111/j.1365-2915.2009.00819.x
- Description: To highlight some issues regarding data quality that are significant in estimating post‐mortem intervals (PMI) from maggots, the developmental constants of thermal summation models for development of Chrysomya megacephala Fabricius (Diptera: Calliphoridae) were calculated from incidental data gathered from 12 published studies, and from data generated specifically for the purpose in a single experiment. The focused experiment involved measuring the timing of five developmental landmarks at nine constant temperatures with a sampling resolution of 6–12 h, which is characteristic of other published studies. Combining data from different studies produced inconsistent results because of statistical noise introduced by (at least) disparities in temporal precision, descriptive statistics, geographical location and rearing diets. A robust experimental design to estimate a developmental model should involve at least six constant temperatures, starting at about 7°C above the relevant developmental zero (D0) and going almost to the upper critical temperature, and a temporal sampling interval with a relative precision of about 10%, which requires sampling about every 2 h until hatching, about every 3 h until first ecdysis and about every 6 h until second ecdysis.
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Deconstructing language myths: which languages of learning and teaching in South Africa
- Authors: Dalvit, Lorenzo , Murray, Sarah , Terzoli, Alfredo
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431260 , vital:72759 , https://d1wqtxts1xzle7.cloudfront.net/91537059/Deconstructing_language_myths_which_languages_of_learning_and_teaching_in_South_Africa.sflb-libre.pdf?1664136385=response-content-disposi-tion=inline%3B+filename%3DDeconstructing_language_myths_which_lang.pdfExpires=1714984902Signature=dj35y~SObsQq0TnqD-oDUj3CX7lgNnKJcMAchC7rarU74xqfrMlVfOwi-MZrNZvWvpxyzquBsmr1veH-ggRVXQP7TX4eKQq3tXV-gJZg3xyo7QJoGwrGPTjC4btF2kNrVJc6TQulzuPFEz47GtjQ6Nint4SmE7A30EMUMd8j25KgCUdtzqwx9kjBs-niKu~z-pk-Xon5YOolMTepbOwNr9wKGj8JafblTdnFs-H8CZ-Et4BD2mYV3GxnR0QLfgawFgDYkOSZnYhkl6wFsXG~Euwlhcvtp0EgUOfP4id~Ov9hhA-rSQxl81X2Dh1BdMuT3GSsK6VNmO7TikSC7NeGlQ__Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA
- Description: In this article we argue for the use of African languages as Languages of Learning and Teaching (LoLT) for native speakers of such language in South Africa. We believe that both public and academic debate is in-fluenced by a set of ‘language myths’: 1) only one language should be used; 2) the earlier one starts using English as LoLT, the better; 3) us-ing English as LoLT improves English proficiency. These myths be seen as a direct manifestation of Western hegemony, and English-functional arguments are often the terms of reference. We will try a dif-ferent approach by highlighting the advantages of using an African lan-guage (ie isiXhosa) as LoLT and, whenever possible, we will try to put English on the ‘defence stand’. The purpose of this paper is not to ad-vocate the substitution of English with an African language. We believe that bilingual education is the appropriate choice for South Africa, but in order to achieve full equality between English and the African lan-guages in education, arguments in support of the latter must be put forward proactively. With our paper, we hope to contribute to this new perspective.
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Deployment and Extension of a Converged WiMAX/WiFi Network for Dwesa Community Area South Africa
- Authors: Ndlovu, N , Terzoli, Alfredo , Thinyane, Mamello
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428479 , vital:72514 , https://citeseerx.ist.psu.edu/document?repid=rep1andtype=pdfanddoi=22468be0252776eabb9e015b51e8e5cf2855ca5f
- Description: As demand for new, reliable, flexible and relatively inexpensive internet access in marginalized rural areas in developing countries increases, there is a need to amalgamate broadband technologies such as WiMAX and WiFi so as to extend the coverage area. Consequently, this will en-able provision of high-speed mobile data and telecommunications ser-vices. This paper describes how WiMAX and WiFi can be merged to-gether, with VSAT technology offering backhaul internet connectivity to provide ever present broadband access. We also look at their respective network applications and how there are going to be used to help support ICT4D activities in these marginalized areas.
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Development and validation of a stability-indicating method for the quantitation of paclitaxel in pharmaceutical dosage forms
- Authors: Mohammadi, Ali , Esimaeili, Farnaz , Dinarvand, Rasoul , Atyabi, Fatemeh , Walker, Roderick B
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184278 , vital:44196 , xlink:href="https://doi.org/10.1093/chromsci/47.7.599"
- Description: A simple, rapid stability-indicating isocratic assay has been developed and validated for the determination of Paclitaxel (PTX) in commercial injection formulations. The assay is performed using a Nucleosil RP-18 (5 µm, 250 × 4.0 mm i.d) column protected by a Nucleosil C18 precolumn (5 µm, 4.0 × 4.0 mm i.d.) with a mobile phase of methanol–water (80:20) and UV detection at 230 nm. The method was found to be specific for PTX in the presence of degradation products with an overall analytical run time of ~ 9 min. Accuracy reported as % bias was found to be 0.1–2.5% bias for all samples tested. Intra-assay precision (repeatability) was found to be 0.22–2.65% RSD, while inter-day precision (intermediate precision) was found to be 1.0–3.0% RSD for the samples studied. The calibration curve was found to be linear with the equation y = 29.78x + 7.65, and a linear regression coefficient of 0.9994 over the concentration range 0.05–20 µg/mL. The limits of quantitation and detection were 0.05 and 0.02 µg/mL, respectively. Taxol (30 mg/5 mL), a commercially available dosage form of PTX, was assayed and 100.6–103.6% of the label claim was recovered.
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Development of Thanatophilus micans (Fabricius 1794)(Coleoptera: Silphidae) at constant temperatures
- Authors: Midgley, John M , Villet, Martin H
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441904 , vital:73933 , https://doi.org/10.1007/s00414-008-0280-0
- Description: Thanatophilus micans is capable of finding corpses at least as quickly as most fly species and, as the most widespread species of the Silphidae in Africa, offers a useful model for estimating post-mortem interval. Larvae were reared at ten constant temperatures from 15°C to 35°C and their length measured at 4, 8, or 12-h intervals depending on their instar. Length generally increased with increased rearing temperature, but decreased at extremely high temperatures. Note was made of the age at which individuals progressed past developmental milestones. Development took longer at lower temperatures. These results are presented as a combined isomegalen and isomorphen diagram. Developmental constants were generated for each milestone using major axis regression. Developmental threshold values did not differ significantly between milestones. Development took longer than in blow flies, but was faster than in Dermestidae. The three models presented here, therefore, cover an important time frame in estimating minimum PMI once fly larvae have matured to the point of leaving a corpse, and, therefore, provide a tool that was not previously available to forensic entomologists.
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Diffraction efficiency and I–V characteristics of metal-free phthalocyanine doped nematic liquid crystals
- Authors: Köysal, Oguz , Okutan, Mustafa , San, S Eren , Nyokong, Tebello , Durmus, Mahmut
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/263511 , vital:53634 , xlink:href="https://doi.org/10.1016/j.matchemphys.2008.10.056"
- Description: The synthesis and characterization of the tetra-4-benzyloxyphenoxy substituted metal-free phthalocyanine (H2Pc) is reported for the first time. Formation of the photoinduced gratings has been experienced in a metal-free phthalocyanine doped nematic liquid crystal (LC) system and its I–V properties are characterized by electrical measurements. Four samples are prepared at different doping percentages and in homogenously aligned sandwiched geometry. We report the results of two set of experiments on these samples. One of them is the grating diffraction experiment for the analysis of optically induced reorientation process which is a basis for possible holographic applications. Accessible diffraction efficiency is found to be linearly increasing as the amount of the phthalocyanine doping rises. In the scope of the other set of measurements I–V peculiarity of the system is also found to be enhanced and linearly dependent on doping.
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Editorial: environmental-education research in the year of COP 15
- Authors: Lotz-Sisitka, Heila , Kronlid, David O
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67356 , vital:29080 , https://www.ajol.info/index.php/sajee/article/view/122784
- Description: publisher version , Introduction: This year there has literally been a cacophony surrounding the implications of climate change, as the world geared up for the 15th Conference of the Parties (COP 15) in Copenhagen, where it was expected that the largest ever gathering of world leaders would sign binding agreements to reduce carbon emissions to keep global temperatures from rising by more than 2⁰C. As we make the final contributions to the refinement of this editorial, late in December 2009, it is concerning to note that this did not happen, that civil society voices were marginalised at the COP 15 and that there has been little progress on a socially just and ecologically sound global climate change deal. The stark reality remains that developing countries – southern African countries in particular – remain most vulnerable to the risks associated with global climate change. Havnevik (2007) stated a while ago that: The ways in which poverty, consumption and climate change are addressed, tend to blur historical, structural and power features underlying global inequalities. This makes possible the focus on market forces, such as carbon trading, to resolve the problems. However, these market solutions will not suffice, and may only delay a real solution, which will then have to be developed in a situation of more acute global social injustice and possibly deeper conflicts … Issues related to inequality, energy and climate are of a global character: there is no longer one solution for the South and one for the North. (18,19) So where does the current state of climate change and the political failures surrounding responses to climate change leave education research in developing and developed nations? What are the implications for environmental education researchers in southern Africa and elsewhere? These are some of the questions pondered in this edition of the Southern African Journal of Environmental Education (SAJEE). As one of us (Kronlid) reflects in a Think Piece in this journal: ‘the world is one and many and … the complexities associated with climate change means that we have a shared global systematic problem manifested in a myriad different concrete ways in people’s everyday life throughout the globe. We need many different kinds and modes of climate change education research’ (Kronlid, this edition).
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Effect of peripheral fused ring substitution on the optical spectroscopy and electronic structure of metal phthalocyanine complexes
- Authors: Chidawanyika, Wadzanai J U , Mack, John , Shimizu, Soji , Kobayashi, Nagao , Nyokong, Tebello
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/263353 , vital:53620 , xlink:href="https://doi.org/10.1142/S1088424609001339"
- Description: In this paper the impact of peripheral substitution with a strongly withdrawing fused ring group on the optical spectroscopy of a metal phthalocyanine complex is analyzed. We report the synthesis of [9 (or 10), 16 (or 17), 23 (or 24)-tri-tert-butylimidophthalocyaninato]zinc(II) (ZnttbIPc), which should eventually prove to be a useful precursor for forming dimeric compounds. The electronic structure is analyzed through a detailed analysis of the UV-visible absorption and magnetic circular dichroism spectra and time-dependent density functional theory calculations. Other than a marked splitting of the Q band, the spectrum is broadly similar to that of ZnPc in terms of the main π → π* electronic bands. The vibrational bands differ markedly in the Q band region when an imido group is added to ligand periphery, relative to what is observed in the case of zinc mononaphthotribenzotetraazaporphyrin (Zn3B1N) with an additional fused benzene ring. The absorption and emission spectra lack mirror symmetry as is the case with ZnPc and thus provide possible evidence for a second set of electronic origins in the Q band region arising from n → π* rather then π → π* transitions.
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Effects of food quality on tissue-specific isotope ratios in the mussel Perna perna
- Authors: Hill, Jaclyn M , McQuaid, Christopher D
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444563 , vital:74251 , https://doi.org/10.1007/s10750-009-9865-y
- Description: Investigations into trophic ecology and aquatic food web resolution are increasingly accomplished through stable isotope analysis. The incorporation of dietary and metabolic changes over time results in variations in isotope signatures and turnover rates of producers and consumers at tissue, individual, population and species levels. Consequently, the elucidation of trophic relationships in aquatic systems depends on establishing standard isotope values and tissue turnover rates for the level in question. This study investigated the effect of diet and food quality on isotopic signatures of four mussel tissues: adductor muscle, gonad, gill and mantle tissue from the brown mussel Perna perna. In the laboratory, mussels were fed one of the two isotopically distinct diets for 3 months.
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Effects of the number of ring substituents of cobalt carboxyphthalocyanines on the electrocatalytic detection of nitrite, cysteine and melatonin
- Authors: Matemadombo, Fungisai , Sehlotho, Nthapo , Nyokong, Tebello
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/263408 , vital:53625 , xlink:href="https://doi.org/10.1142/S108842460900125X"
- Description: Cobalt phthalocyanine (CoPc), cobalt tetracarboxy phthalocyanine (CoTCPc) and cobalt octacarboxy phthalocyanine (CoOCPc), adsorbed onto glassy carbon electrodes, have been used for the electrocatalytic detection of nitrite, L-cysteine and melatonin. The modified electrodes electrocatalytically detected nitrite around 800 mV vs.Ag|AgCl, a value less positive compared to that of an unmodified glassy carbon electrode (at 950 mV vs.Ag|AgCl) and also gave detection limits in the 10-7 M range for nitrite detection. L-cysteine was detected by the modified electrodes at potentials between 0.50 to 0.65 V vs.Ag|AgCl, with L-cysteine detection limits also in the 10-7 M range. The detection limits for melatonin ranged from 10-7 to 10-6 M. CoPc-modified electrodes displayed good separation of interferents (tryptophan and ascorbic acid) in the presence of melatonin. Analyses of commercial melatonin tablets using modified electrodes gave excellent agreement with manufacturer's value for all modified electrodes of this work.
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Electrostatic self-assembly of quaternized 2,(3)-tetra (oxo-pyridine) phthalocyaninato chloroindium (III) with a series of tetrasulfonated phthalocyanines
- Authors: George, Reama C , Durmus, Mahmut , Egharevba, Gabriel O , Nyokong, Tebello
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/263330 , vital:53618 , xlink:href="https://doi.org/10.1016/j.poly.2009.07.035"
- Description: The self-assembly of oppositely charged phthalocyanines, fabricated using quaternized 2,(3)-tetra(oxo-pyridine) phthalocyaninato chloroindium (III) (QInPyPc) as the positively charge molecule and a series of tetrasulfonate phthalocyanine (MTSPc), M = 2H, Mn, Fe, Co and Ni as negatively charged molecules are reported. The self-assembly results in the formation of heteroaggregates. The metallated sulfonated phthalocyanines form nanorod and nanoleaf shaped structures as evidenced by transmission electron microscopy (TEM). The UV–Vis spectra showed blue shifted Q bands, suggesting that these structures were in a face-to-face arrangement. The Raman spectra of the heteroaggregates showed shifting compared to the spectra of the precursors.
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eServices provisioning in a community development context through a JADE MAS platform
- Authors: Thinyane, Mamello , Terzoli, Alfredo , Clayton, Peter G
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430836 , vital:72720 , 10.1109/ICTD.2009.5426697
- Description: A growing proliferation of ICT4D interventions has necessitated the ex-ploration of innovative solutions for the provisioning of eServices in ru-ral, marginalized communities. The challenges currently faced in these interventions include: situating the developed applications within the cultural and ethnographic context of the target communities, integrating greater levels of granularity and flexibility within the applications for in-creased context sensitivity, handling the intermittence and instability of supporting infrastructural services. These are the challenges that we address in the context of ICT4D intervention undertaken in a rural community in the Eastern Cape province of South Africa. We explore the design and implementation of a Multi-Agent System (MAS) for this community as a platform for provisioning of context-sensitive eServ-ices, and highlight some observations with regards to the applicability and adequacy of the solution.
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Establishment of translocated populations of smallmouth yellowfish, Labeobarbus aeneus (Pisces: Cyprinidae), in lentic and lotic habitats in the Great Fish River system, South Africa
- Authors: Weyl, Olaf L F , Stadtlander, Timo , Booth, Anthony J
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124418 , vital:35607 , https://doi.org/10.3377/004.044.0109
- Description: As a result of numerous introductions and translocations of fishes, South Africa has recently been identified as a fish invasion hotspot (Leprieur et al. 2008). In freshwater ecosystems invasion by alien species is considered a leading mechanism driving environmental change (Clavero & Garcia- Berthou 2005; Garcia-Berthou et al. 2005). In South Africa, documented effects of fish invasions include the extirpation of indigenous fishes through predation (Cambray 2003), changes in invertebrate community structure (Lowe et al. 2008) and hybridization (Canonico et al. 2005). As a result, the management of alien species is a high national priority (National Environmental Management: Biodiversity Act 2004). Such management requires an understanding of the biology, ecology and establishment success of fishes outside their native range.
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Evaluating text preprocessing to improve compression on maillogs
- Authors: Otten, Fred , Irwin, Barry V W , Thinyane, Hannah
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430138 , vital:72668 , https://doi.org/10.1145/1632149.1632157
- Description: Maillogs contain important information about mail which has been sent or received. This information can be used for statistical purposes, to help prevent viruses or to help prevent SPAM. In order to satisfy regula-tions and follow good security practices, maillogs need to be monitored and archived. Since there is a large quantity of data, some form of data reduction is necessary. Data compression programs such as gzip and bzip2 are commonly used to reduce the quantity of data. Text preprocessing can be used to aid the compression of English text files. This paper evaluates whether text preprocessing, particularly word replacement, can be used to improve the compression of maillogs. It presents an algorithm for constructing a dictionary for word replacement and provides the results of experiments conducted using the ppmd, gzip, bzip2 and 7zip programs. These tests show that text prepro-cessing improves data compression on maillogs. Improvements of up to 56 percent in compression time and up to 32 percent in compression ratio are achieved. It also shows that a dictionary may be generated and used on other maillogs to yield reductions within half a percent of the results achieved for the maillog used to generate the dictionary.
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Exploratory mathematics talk in a second language: a sociolinguistic perspective:
- Authors: Graven, Mellony , Robertson, Sally-Ann
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/69907 , vital:29594 , https://doi.org/10.1007/s11858-018-0952-2
- Description: This paper illuminates challenges confronting teachers and students at the literacy/numeracy interface in contexts where students have not developed sufficient English language proficiency to be learning mathematics through English but, due to socio-politically and economically driven perceptions are being taught in English. We analyse transcript data of classroom talk in a South African grade 4 mathematics lesson on fractions. Together with interview data, the lesson data highlight some of the consequences students’ diminished access to their home language appear to have on their access to mathematical meaning-making.
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Exploring Learner Participation in Waste-Management Activities in a Rural Botswana Primary School
- Authors: Silo, Nthalivi
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/386509 , vital:68148 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122820"
- Description: In Botswana, participation in environmental learning activities has been perceived as a central component of environmental education in formal education. Driven by the need to implement the objective of making the participatory approach part of the infusion of environmental education in the school curriculum as prescribed by the infusion policy, Botswana schools have come up with initiatives to involve learners in environmental education activities that seem to have ‘a direct, perceived benefit to the learners’ (NEESAP, 2007:9). Within this approach it is expected that learners should participate in these activities. However, Ketlhoilwe (2007) revealed that there has been a normalisation of environmental education into existing school culture through equating waste-management activities with environmental education. This generally entails cleaning activities by learners to maintain ‘clean schools’, which is directly associated with environmental education. Drawing from detailed case study data in one rural primary school with Standard 6 learners, I used Cultural Historical Activity Theory to investigate and explain how learners participate in these waste-management activities. Findings from this study revealed that attempts by teachers to meet the policy imperative through prescription of rules, and ascribing roles to learners in waste-management activities, create tensions. This gave rise to an elusive object of learner participation, as the purpose for their participation in these activities is not clear.
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Extending the NFComms: framework for bulk data transfers
- Authors: Nottingham, Alastair , Irwin, Barry V W
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430164 , vital:72670 , https://doi.org/10.1145/1632149.1632170
- Description: Packet analysis is an important aspect of network security, which typi-cally relies on a flexible packet filtering system to extrapolate important packet information from each processed packet. Packet analysis is a computationally intensive, highly parallelisable task, and as such, clas-sification of large packet sets, such as those collected by a network tel-escope, can require significant processing time. We wish to improve upon this, through parallel classification on a GPU. In this paper, we first consider the OpenCL architecture and its applicability to packet analy-sis. We then introduce a number of packet demultiplexing and routing algorithms, and finally present a discussion on how some of these techniques may be leveraged within a GPGPU context to improve packet classification speeds.
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Film Review: Hollywood on Safari
- Authors: Amner, Roderick J
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142680 , vital:38101 , https://doi.org/10.1386/jams.1.2.335_4
- Description: Film Review: Hollywood on Safari.
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Flies in the ointment a morphological and molecular comparison of Lucilia cuprina and Lucilia sericata (Diptera: Calliphoridae) in South Africa
- Authors: Tourle, Robyn , Downie, Douglas A , Villet, Martin H
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442156 , vital:73963 , https://doi.org/10.1111/j.1365-2915.2008.00765.x
- Description: Complementary nuclear (28S rRNA) and mitochondrial (COI) genes were sequenced from blowflies that phenotypically resembled Lucilia cuprina (W.), Lucilia sericata (Meigen) or exhibited characters of both species. The aim was to test a long‐held hypothesis that these species hybridize under natural conditions in South Africa (Ullyett, 1945). Blowflies were obtained predominantly from the Cape Town metropolitan area, but reference samples were acquired for L. sericata from Pretoria. Several L. cuprina‐like flies were shown to possess a conflicting combination of nuclear and mitochondrial genes that has also been seen in Hawaiian specimens. Homoplasy, sampling of pseudogenes, hybridization and incomplete lineage sorting are discussed as possible hypotheses for the pattern and the latter is concluded to represent the most likely explanation.
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