Descriptive Chemistry: PAC 113F
- Authors: Hasheni, T , Mrwebi, M , Tichagwa, L , Ajibade, A P
- Date: 2008-07
- Language: English
- Type: Examination paper
- Identifier: vital:17825 , http://hdl.handle.net/10353/d1010378
- Description: Descriptive Chemistry: PAC 113F, supplementary degree examination July 2008.
- Full Text: false
- Date Issued: 2008-07
Determination of the optimal water temperature for the culture of juvenile dusky kob Argyrosomus japonicus Temminck and Schlegel 1843:
- Authors: Collett, Paul D , Vine, Niall G , Kaiser, Horst , Baxter, Jeremy
- Date: 2008
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142804 , vital:38118 , DOI: 10.1111/j.1365-2109.2008.01960.x
- Description: The effects of temperature on growth, food conversion ratio (FCR) and feeding intensity of juvenile dusky kob Argyrosomus japonicus (23.7±2.6 g fish−1) were assessed over the temperature range 17.5–28.5°C in a 42 day growth trial. Growth increased with increasing temperature up to an optimum after which it declined. Specific growth rates were 2.05% and 1.2% day−1 for the fastest (25.3 °C) and the slowest (17.5 °C) treatments respectively. Food conversion ratio peaked at a lower temperature than growth. Optimal (0.72 kg kg gain−1) and least efficient (1.40 kg kg gain−1) FCR were found at 21.7 and 17.5°C respectively. Feeding intensity was linearly related to temperature within the range of 17.5–28.5°C. These results corresponded to the thermal preference (25–26.4°C) and natural temperature distribution (12–28°C) of South African dusky kob. Determination of the temperature range that does not limit growth is a prerequisite to assess the relationship between growth and environmental variables such as light intensity, feeding regime and stocking density. Consequently, experiments to determine the effects of these environmental variables on growth and aquaculture potential of dusky kob should be conducted at 24–26°C.
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- Date Issued: 2008
Marine reservoir corrections : St. Helena, South Atlantic Ocean
- Authors: Lewis, Colin A , Reimer, P J , Reimer, R W
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6701 , http://hdl.handle.net/10962/d1006737
- Description: We present the first marine reservoir age and ∆R determination for the island of St. Helena using marine mollusk radiocarbon dates obtained from an historical context of known age. This represents the first marine reservoir age and ∆R determination in the southern Atlantic Ocean within thousands of kilometers of the island. The depletion of 14C in the shells indicates a rather larger reservoir age for that portion of the surface Atlantic than models indicate. The implication is that upwelling old water along the Namibian coast is transported for a considerable distance, although it is likely to be variable on a decadal timescale. An artilleryman’s button, together with other artifacts found in a midden, demonstrate association of the mollusk shells with a narrow historic period of AD 1815–1835.
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- Date Issued: 2008
Karyology of three evolutionarily hexaploid southern African species of yellowfish, Labeobarbus Rüppel, 1836 (Cyprinidae)
- Authors: Naran, D , Skelton, Paul H , Villet, Martin H
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6855 , http://hdl.handle.net/10962/d1011138 , http://dx.doi.org/10.3377/1562-7020(2007)42[254:KOTEHS]2.0.CO;2
- Description: The karyotypes of three species of yellowfish, namely Labeobarbus marequensis (A. Smith, 1841), L. capensis (A. Smith, 1841) and L. polylepis (Boulenger, 1907), were examined by Giemsa staining using an approach improved for the description of high chromosome numbers. In each case, 2n = 150; no heteromorphic chromosomes were detected; chromosomes in all morphological categories ranged smoothly from large to small, with no distinctly large submetacentric pairs; and metacentric chromosomes showed little variation in size. Labeobarbus marequensis had 26 metacentric (m), 44 submetacentric (sm), 42 subtelocentric (st) and 38 acrocentric (a) chromosomes and a fundamental number (FN) of 262; L. capensis had 16 m, 58 sm, 42 st and 34 a chromosomes and FN = 266; and L. polylepis had 18 m, 60 sm, 42 st and 30 a chromosomes and FN = 270. These results, combined with published literature, imply that Labeobarbus Rüppel, 1836 is an evolutionarily hexaploid African lineage and support its removal from synonymy with the evolutionarily tetraploid Asian genus Tor Gray, 1834. A review of fundamental numbers for conspecific Labeobarbus species examined in different studies implicated karyological technique as a confounding factor in assessing details of karyotypes, leading to recommendations for future karyological studies of barbine fishes. Potential synapomorphies are pointed out in karyological characters of species within Labeobarbus.
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- Date Issued: 2007
Load carrying : in situ physiological responses of an infantry platoon
- Authors: Scott, Patricia A , Ramabhai, L
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6753 , http://hdl.handle.net/10962/d1009333
- Description: Morphological diversity is the source of differential stress when heavy work must be done by groups, as in the carrying of military equipment by a platoon. In this study 10 infantrymen each carried 40.5kg at the same pace over a 12km route on one day and 37% of personal body weight on another occasion. Physiological and perceptual responses indicated less stress was experienced when loads were normalised for morphological differences between the troops.
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- Date Issued: 2007
Rhodes University : into 2007 and beyond
- Authors: Badat, Saleem
- Date: 2007
- Subjects: Rhodes University
- Language: English
- Type: text
- Identifier: vital:7655 , http://hdl.handle.net/10962/d1015783
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- Date Issued: 2007
A history of southern African research relevant to forensic entomology
- Authors: Williams, K A , Villet, Martin H
- Date: 2006
- Language: English
- Type: text , Article
- Identifier: vital:6909 , http://hdl.handle.net/10962/d1011862
- Description: Entomological forensic evidence has been used in southern Africa for decades but explicitly forensic research began in southern Africa only 26 years ago. Although applicable local research has accumulated since 1921, it is scattered in a diverse literature or unpublished. Some overseas research has also touched on local species. This review uses a historical approach to synthesize the southern African literature and to illustrate the cross-disciplinary, opportunistic nature of forensic entomology. Distinct phases of research focused on agriculture (1921-1950), medicine (1952- 1965), ecology (1968-1990) and forensics (1980-2005), but systematics spanned the entire period and tended to be ad hoc. Few scientists were involved, situated at geographically distant locations and with widely disparate research interests. The review concludes with an overview of southern African entomologists who have been involved in medico-legal investigations, and a critical evaluation of the past and future of the discipline locally.
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- Date Issued: 2006
African Coelacanth Ecosystem Programme: An overview of the conference contributions
- Authors: Ribbink, Anthony J , Roberts, M
- Date: 2006
- Language: English
- Type: text , Article
- Identifier: vital:7127 , http://hdl.handle.net/10962/d1010637
- Description: Latimeria chalumnae is the icon for the multidisciplinary, multinational African Coelacanth Ecosystem Programme (ACEP) dedicated to improving the understanding of biological and other processes that support marine life. This article provides an overview of contributions made at a conference hosted by ACEP at the end of 2003. It also reviews significant developments regarding coelacanth conservation which have taken place since the conference. Delegates at the meeting concluded that the integrated regional,ecosystem approach that had been adopted by ACEP should continue. Underwater observation and exploration, however, should be supplemented by more experimental and technical analyses in order to answer longstanding questions related to coelacanths and other organisms.
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- Date Issued: 2006
Ceropegia macmasteri (Apocynaceae-Asclepiadoideae-Ceropegieae), a new species from Eastern Cape, South Africa
- Authors: Dold, Anthony P
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6515 , http://hdl.handle.net/10962/d1005943 , http://dx.doi.org/10.1016/j.sajb.2005.06.005
- Description: Ceropegia macmasteri, a new species from Cathcart in the Eastern Cape Province of South Africa, is only known from a single population in Dohne sourveld grassland where it occurs with another rare local endemic species of the Ceropegieae, Brachystelma cathcartense R.A.Dyer. The new species, an herbaceous grassland plant with a tuberous rootstock, most closely resembles C. stentiae E.A.Bruce, but is distinguished by its linear-erect corona lobes and inner corona conniving to form a central column.
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- Date Issued: 2006
Exploitation status of infralittoral abalone (Haliotis midae) and alikreukel (Turbo sarmaticus) in the southern section of the Eastern Cape coast, South Africa
- Authors: Proudfoot, Lee-Anne , Kaehler, Sven , McGarry, Dylan K , Uppink, P A , Aereboe, Michael , Morris, K M
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6915 , http://hdl.handle.net/10962/d1011878
- Description: Intertidal size-frequency distributions and densities for Haliotis midae and Turbo sarmaticus were examined at 10 sites experiencing varying pressure of human exploitation along the southern section of the Eastern Cape coast, South Africa. Target species' densities and maximum sizes were related both to the numbers of collectors on the shore and to indirect indicators of exploitation such as number of households in the vicinity and distance to the nearest beach access point. For both species, there was variation in density (P < 0.05) and size (P < 0.05) among sites, with densities ranging between 0.03-2.23 m^(-2) and 0.07-4.93 m^(-2) for H. midae and T. sarmaticus, respectively. Maximum sizes ranged between 49.4-153.5 mm (H. midae) and 28.3-104.4 mm (T. sarmaticus) shell length. Population parameters such as mean maximum size and total density were significantly negatively related to exploitation indicators for both species. In addition, densities of sexually mature and legal-size individuals of T. sarmaticus were significantly negatively related to the number of households. However, only for H. midae were densities of subadults significantly negatively related to the number of collectors, suggesting that reproduction of abalone may be suppressed at the most exploited sites. Exploitation of T. sarmaticus tends to be localized near population centres, whereas H. midae is collected over a larger range of sites. Overall, T. sarmaticus is less affected by exploitation than H. midae.
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- Date Issued: 2006
The relationship between human exploitation pressure and condition of mussel populations along the south coast of South Africa
- Authors: Rius, Marc , Kaehler, Sven , McQuaid, Christopher D
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6913 , http://hdl.handle.net/10962/d1011876
- Description: Human exploitation of intertidal organisms in South Africa is an ancient activity based principally on mussels. We studied mussel populations and patterns of exploitation along a 160-km stretch of the south coast. Photographs (100 per site) were taken of the intertidal rocks at each of 14 sites, covering a range of exploitation intensities. Percentage cover was negatively correlated with number of mussel patches and positively correlated with mean shell width. PCA analysis identified groups of sites: a) accessible and unprotected sites: low cover, small mussels, patchy distribution; b) inaccessible sites and sites next to, or within, nature reserves: high percentage cover, large animals, less patchy distributions. Affluent coastal settlements also seem to confer protection against harvesting. Harvester distribution was examined by aerial surveys and combined with information on distance to the nearest beach access point and number of households within 7 km for each site. Sites within reserves and inaccessible sites had low densities of collectors, whereas sites near urban areas and in the Ciskei had the highest densities. All correlations between indicators of human exploitation and condition of mussel populations were non-significant. However, number of collectors showed positive trends with number of patches and negative trends for the two other variables. The results indicate much lower levels of exploitation than in the neighouring Transkei region, and suggest a high degree of background variability in mussel population structure.
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- Date Issued: 2006
Academic Practices and Reasoning: APR 111
- Authors: Jadhunundhan, R , Rautenbach, E
- Date: 2005-06
- Language: English
- Type: Examination paper
- Identifier: vital:18265 , http://hdl.handle.net/10353/d1011261
- Description: Academic Practices and Reasoning: APR 111, examination June 2005.
- Full Text: false
- Date Issued: 2005-06
"The French Imperial Nation-State":
- Authors: Bischoff, Paul, 1954-
- Date: 2005
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/161376 , vital:40621
- Description: Book Review. The French Imperial Nation-State. By G Wilder (2005).
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- Date Issued: 2005
Mainstreaming Gender Standards in Collective Bargaining
- Authors: COSATU
- Date: 2005
- Subjects: COSATU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/154231 , vital:39624
- Description: The apartheid system and capitalism used the patriarchal nature of the South African society through the sexual division of labour and divided the labour force on the grounds of class, race and gender to exploit them for cheap labour to maximize their profits. They exploited the notion of men as the head of the family to force men to become migrant labourers and disregarded the reproductive and domestic role of women.
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- Date Issued: 2005
Monitoring the oceanic flow between Africa and Antarctica: report of the first Good Hope cruise
- Authors: Ansorge, Isabelle J , Speich, S , Lutjeharms, Johan R E , Goni, G J , Rautenbach, C J de W , Froneman, P William , Rouault, M , Garzoli, S
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6832 , http://hdl.handle.net/10962/d1007568
- Description: The Southern Ocean plays a major role in the global oceanic circulation, as a component of the Meridional Overturning Circulation, and it is postulated that it has a great influence on present-day climate. However, our understanding of its complex three-dimensional dynamics and of the impact of its variability on the climate system is rudimentary. The newly constituted, international GoodHope research venture aims to address this knowledge gap by establishing a programme of regular observations across the Southern Ocean between the African and Antarctic continents. The objectives of this programme are fivefold: (1) to improve understanding of Indo-Atlantic inter-ocean exchanges and their impact on the global thermohaline circulation and thus on global climate change; (2) to understand in more detail the influence these exchanges have on the climate variability of the southern African subcontinent; (3) to monitor the variability of the main Southern Ocean frontal systems associated with the Antarctic Circumpolar Current; (4) to study air-sea exchanges and their role on the global heat budget, with particular emphasis on the intense exchanges occurring within the Agulhas Retroflection region south of South Africa, and (5) to examine the role of major frontal systems as areas of elevated biological activity and as biogeographical barriers to the distribution of plankton. We present here preliminary results on the physical and biological structure of the frontal systems using the first GoodHope transect that was completed during February-March 2004.
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- Date Issued: 2005
Wireless communication for previously disadvantaged secondary schools in Grahamstown, South Africa.
- Authors: Brandt, Ingrid , Terzoli, Alfredo , Hodgkinson-Williams, Cheryl
- Date: 2005
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427615 , vital:72451 , https://citeseerx.ist.psu.edu/document?repid=rep1andtype=pdfanddoi=2520d49f684e821c84350ae8c504572f35186d2f
- Description: With an alarmingly low teledensity in South Africa, less than 5% in some rural areas, and not much hope of further wired infrastructure, as the costs incurred are high compared to potential revenue, wireless connec-tivity could be a great asset and service in South Africa. This paper looks at how wireless communication technologies, 802.11, WiMAX and VSAT, can be used to allow broadband connectivity of schools to the Internet, with special reference to experimental work that is being done in Grahamstown schools.
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- Date Issued: 2005
Evidence for Archaean lamprophyre from the Kaapvaal Craton, South Africa
- Authors: Prevec, S A , Anhaeusser, C R , Poujol, M
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6739 , http://hdl.handle.net/10962/d1007555
- Description: A suite of mafic dykes occurs as a late component in a wellcharacterized trondhjemite–tonalite–diorite–granodiorite assemblage in the Johannesburg Dome of the central Kaapvaal Craton, southern Africa. The dykes have been subdivided into two sets, based on their orientation, and major and trace element geochemistry. Set 1 dykes are characterized by elevated SiO2, Al2O3 and TiO2, and particularly by enriched LILE and HSFE (e.g. Zr > 200 ppm, Nb > 20 ppm, Ba > 300 ppm), higher than in any of the accompanying felsic rocks. REE and trace element values for Set 1 dykes are similar to those for calc-alkaline lamprophyres. The Set 2 dykes have similar trace element distributions, but are significantly less enriched in general, and are broadly tholeiitic in composition, with enriched MgO (>11 wt. percentage) indicative of an olivine–phyric tholeiitic basaltic protolith. Field relationships and available U–Pb zircon geochronology indicate that the dykes are contemporaneous with components of the trondhjemitic host rocks, and with late granodiorites. The geochemical, geochronological and field petrological setting indicates partial melting of basaltic and eclogitic lithosphere at c. 3120 Myr ago in the basal Kaapvaal Craton, and subsequent emplacement into pre-existing c. 3430 Myr tonalitic to dioritic crust.
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- Date Issued: 2004
In situ feeding rates of the copepods, Pseudodiaptomus hessei and Acartia longipatella, in a temperate, temporarily open/closed Eastern Cape estuary
- Authors: Froneman, P William
- Date: 2004
- Language: English
- Type: text , Article
- Identifier: vital:6901 , http://hdl.handle.net/10962/d1011754
- Description: Size-fractionated chlorophyll-a (chl-a) concentrations and the in situ grazing rates of the copepods, Pseudodiaptomus hessei and Acartia longipatella, were assessed seasonally at the temporarily open/closed Kasouga estuary situated along the southeast coast of southern Africa. Total integrated chl-a concentration ranged between 1.17 and 12.18 mg chl-a m^(–3) and was always dominated by small phytoplankton cells (<20 μm), which comprised up to 86% (range 64–86%) of the total pigment. Total zooplankton abundance ranged between 2676 and 62 043 individuals m^(–3). These copepods numerically dominated the zooplankton counts, accounting for between 79% and 91% of the total. Gut pigment concentrations of the two species at night were significantly higher than the daytime values (P<0.05 in all cases). The observed pattern could be related to the marked diurnal vertical migration patterns exhibited by the copepods. Gut evacuation rates of P. hessei during the study ranged between 0.29 and 0.77 h^(–1) and between 0.39 and 0.58 h^(–1) for A. longipatella. The rate of gut pigment destruction for P. hessei and A. longipatella ranged between 55% and 81% and between 88% and 92% of the total chl-a ingested, respectively. The combined grazing impact of the two copepods ranged between 0.65 and 4.37 mg chl-a m^(–3), or between 4.3% and 35.9% of the available chl-a in the water column. Variations in the grazing activity of the two species could be attributed largely to seasonality in water temperature and shifts in the phytoplankton community structure and zooplankton abundance.
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- Date Issued: 2004
Livelihood benefits from the local level commercialization of savanna resources: a case study of the new and expanding trade in marula (Sclerocarya birrea) beer in Bushbuckridge, South Africa
- Authors: Shackleton, Sheona E
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6649 , http://hdl.handle.net/10962/d1007060
- Description: In the face of economic hardship and poverty, rural people in South Africa and globally are increasingly turning to the natural resource base to generate income. One product that has recently entered into local commercial markets is a traditional alcoholic beverage brewed from the fruits of Sclerocarya birrea (marula), commonly known as marula beer. It was rarely traded in the past due to customary taboos prohibiting its sale. In Bushbuckridge, Limpopo province, rural women have been selling marula beer in the business centres of the district and along the roadside since 1998. A survey of these markets was undertaken in 2002, to discover the commercialization process involved, from raw material harvesting to marketing, and to assess the importance of the trade for household livelihoods and poverty alleviation. Fifty-one traders were interviewed, who indicated that the sale of marula beer provides a vital source of income to several hundred households from amongst the poorest sector of the Bushbuckridge community. Of particular importance were the low barriers of entry to the trade, as the resource is abundant and freely accessible and there are few costs to produce marula beer. Incomes earned were modest, averaging a net R500 per season, and highly seasonal, but came at a critical point in the household calendar, after the festive season and when cash was required for the new school year. Income bridging, livelihood diversification, and the provision of a safety net for the poorest members of society are some of the key benefits of the beer trade.
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- Date Issued: 2004
Pictograms for conveying medicine instructions: comprehension in various South African language groups
- Authors: Dowse, Roslind , Ehlers, Martina S
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6354 , http://hdl.handle.net/10962/d1006038
- Description: The comprehension of medicine instructions is essential for the safe and effective use of medicines. In cases where low literacy constitutes a possible barrier to understanding written medicine information fully, the inclusion of pictograms may facilitate comprehension. Twenty-three internationally available pictograms and 23 corresponding locally developed images were evaluated in 304 low-literate respondents from eight different South African language groups. Demographic data were collected and an English literacy test was administered to those respondents who had stated that they could read English. Interviewees were shown the 46 pictograms in random order and were asked for their interpretation. Preference for either the international or local version was assessed. Correct interpretation of individual pictograms ranged from 14% to 97%. Images which had been developed locally were more successful in eliciting correct interpretations than those obtained from an international source (USP pictograms). Only 2 of the 23 USP pictograms achieved the 85% criterion of the American National Standards Institute compared with 12 of 23 locally developed counterparts. Local pictograms were preferred over the American ones in all cases. Standard of education had a significant influence on interpretation, whereas no significant differences in interpretation could be attributed to cultural diversity between the African language groups. Almost all respondents (98%) reacted positively to the idea of having pictograms on their medicine labels. The success of the local pictograms highlighted the value of a rigorous and consultative design and test process. Results from one African language group can reliably be extrapolated to other groups in South Africa.
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- Date Issued: 2004