https://vital.seals.ac.za/vital/access/manager/Index ${session.getAttribute("locale")} 5 Some theoretical considerations in applying cost-benefit analysis to Black education in South Africa https://vital.seals.ac.za/vital/access/manager/Repository/vital:1047 Wed 12 Oct 2022 11:38:37 SAST ]]> An interpretive use of drawings to explore the lived experiences of orphaned children living with HIV/AIDS in South Africa https://vital.seals.ac.za/vital/access/manager/Repository/vital:3099 Wed 12 May 2021 19:42:01 SAST ]]> Phylogenetics of the keratin-feeding beetle family Trogidae (Coleoptera: Scarabaeoidea) https://vital.seals.ac.za/vital/access/manager/Repository/vital:20037 Wed 12 May 2021 19:35:03 SAST ]]> Understanding the reading practices of Fort Hare students https://vital.seals.ac.za/vital/access/manager/Repository/vital:21197 Wed 12 May 2021 18:31:43 SAST ]]> The early proterozoic Makganyene glacial event in South Africa : its implication in sequence stratigraphy interpretations, paleoenvironmental conditions and iron and manganese ore deposition https://vital.seals.ac.za/vital/access/manager/Repository/vital:5039 Wed 12 May 2021 18:14:11 SAST ]]> The pyrrolizidine alkaloids of Senecio chrysocoma and Senecio paniculatus https://vital.seals.ac.za/vital/access/manager/Repository/vital:4339 Wed 12 May 2021 17:44:25 SAST ]]> Synthesis, characterisation and biological activity of 2-(methylthiomethyl)anilines, 2-(methylthio)anilines, their Schiff-base derivatives and metal(II) (Co, Ni, Cu) complexes https://vital.seals.ac.za/vital/access/manager/Repository/vital:4562 Co(II) > Ni(II). The Schiff-base derivatives were prepared from the ligands and para-methoxysalicylaldehyde and their Cu(II) complexes were synthesized in order to determine their biological activity. The Schiff-base ligands were found to be less active than their parent ligands. The Cu(II) complexes are not soluble in water, DMSO or DMF, as a result and could not be evaluated for their biological activity. Based on the good results from the antimicrobial evaluation, the antiplasmodial activity of some of the Co(II), Ni(II) and Cu(II) complexes of the thiomethylated ligands against Plasmodium falciparum (FCR-3) was determined. At 50 μM concentration level, the Cu(II) complexes show activity equal or better than the prophylactic chloroquine. The Cu(II) complexes with the methoxy-substituted demonstrated exceptional activity but their Co(II) and Ni(II) analogues did not show any activity. The cytotoxicity of the active Cu(II) complexes at 50 μM concentration was determined against the breast cancer cell line (MDA-MB-231). The compounds destroyed the cancer cell in the range of 28–40%, thus showing their preferred activity against the parasitic cell instead of the cancer cell. The selectivity demonstrated by these compounds have shown them to be potential antimalarial agents and this could be further investigated.]]> Wed 12 May 2021 17:24:20 SAST ]]> Collaborative teacher participation in curriculum development : a case study in junior secondary general science (January 1991-November 1991) https://vital.seals.ac.za/vital/access/manager/Repository/vital:1451 Wed 12 May 2021 17:18:35 SAST ]]> The development and failure of the Eastern Cape separatist movement with special reference to John Paterson https://vital.seals.ac.za/vital/access/manager/Repository/vital:2593 Wed 12 May 2021 16:01:32 SAST ]]> An investigation of parental involvement in the development of their children's literacy in a rural Namibian school https://vital.seals.ac.za/vital/access/manager/Repository/vital:1638 Wed 12 May 2021 15:49:28 SAST ]]> Ecological consequences of non-native fish invasion in Eastern Cape headwater streams https://vital.seals.ac.za/vital/access/manager/Repository/vital:29380 20% habitat loss due to invasion). Upstream invasion by centrarchids isolated and fragmented P. afer populations into headwater refugia, while top down invasion by salmonids excluded B. trevelyani from invaded, more pristine stream reaches, by forcing the species into degraded unsuitable lower stream reaches. Predation also disrupted population processes such as adult dispersal for P. afer, and centrarchid-invaded zones acted as demographic sinks, where adults dispersing through invaded reaches were rapidly depleted. While the Mandela lineage of P. afer exhibited little within or between drainage genetic structuring, B. trevelyani was >4% divergent between drainages, and up to 2% divergent between streams within the Keiskamma River system (Chapter 7). The distribution of genetic diversity for B. trevelyani also indicated that the loss of diversity was imminent without immediate conservation interventions. This thesis has provided conclusive evidence that native fishes are vulnerable to invasion and that non-native predatory fishes have significant impacts on native fishes in Eastern Cape headwater streams. If management and conservation measures are implemented, the unwanted introduction and spread of non-native fishes may be restricted, allowing native fishes opportunities for recovery.]]> Thu 13 May 2021 07:28:56 SAST ]]> Assessment of the impact of land use practices on vegetation , soil and carbon-nitrogen sequestration potential in Mopane rangelands of Central Northern Namibia https://vital.seals.ac.za/vital/access/manager/Repository/vital:39100 0.05) between the three land management systems. Woody plant density of height classes were significantly different (P < 0.05) between three land management systems. The abundance of seedlings, saplings and young shrubs were significantly greater (P < 0.05) in the ranch than the game reserve and communal area. The mature trees had a significantly greater density (P < 0.05) in the game reserve than the ranch and communal area. Soil analysis results showed that Magnesium (Mg), Potassium (K), Manganese (Mn) and Copper (Cu) had similar (P > 0.05) concentrations in soils obtained from all land management systems in both seasons. Soil Calcium (Ca) levels showed differences between land management systems in winter only being greater (P < 0.001) in the game reserve than the ranch and the communal lands. Soil Phosphorus (P) and Iron (Fe) also showed variations between land management systems in winter being significantly greater (P < 0.001) in the ranch than the other land management systems. The concentration of soil K differed between the two seasons in soils collected from the ranch and the communal lands, being greater (P < 0.001) in winter than summer seasons. Soil Zinc (Zn) also showed differences between land management systems in summer being greater (P < 0.001) in the game reserve than in the ranch and communal land. Seasonal variations were observed in soil P level of samples collected from the ranch being greater (P < 0.001) in winter than summer season. The concentration of soil Zn was higher (P < 0.001) in the soil collected from the game reserve and the ranch in summer than winter season. Woody forage analysis results showed that browse samples harvested from the ranch had greater (P < 0.001) Nitrogen (N) level than the other land management systems in both seasons. The browse samples harvested from the game reserve had greater (P < 0.001) Ca level than the other land management systems in winter season only. The level of P showed variations (P < 0.05) between land management systems in samples harvested during winter only being greater (P < 0.001) in samples from the ranch than the other land management systems. Similarly, browse harvested during winter showed significant differences (P < 0.05) in K levels being lowest in samples collected from game reserves, where the Ca level was greatest. Browse samples collected from the communal land and the ranch had the lowest Mg levels in summer and winter seasons, respectively. In all management systems, browse harvested during summer had greater (P < 0.001) N and P levels than those harvested in winter, and the reverse holds true for K and Ca levels. Browse samples harvested during winter had greater (P < 0.001) Mn levels in samples from the communal area and game reserve than the ranch, but in summer, the game reserve had higher Mn level than the other two sites. Browse samples harvested during winter only showed differences (P < 0.05) in Cu and Zn levels being greatest (P < 0.001) in samples collected from ranch and game reserves. In all management systems, browse samples harvested during winter had greater (P < 0.001) Fe, Mn, Zn and Cu (except for the game reserve and communal land) levels than those harvested in summer. Herbaceous analysis results showed that samples harvested in summer from the game reserve and ranch had greater (P < 0.001) TOC levels than the communal area, but in winter, samples from the game reserve and ranch had similar TOC levels, except for communal areas that had no herbaceous vegetation. Herbaceous samples harvested in winter from the ranch had greater (P < 0.001) TN levels than the game reserve, and that made the C:N ratio higher (P < 0.001) in the game reserve. Woody foliar samples harvested in winter from the game reserve and communal lands had greater (P < 0.001) TOC than the ranch. Values on C:N ratio showed that in winter, the communal and ranch had greater (P < 0.001) C:N than the game reserve, but in summer, the ranch had higher (P < 0.001) C:N than the game reserve and communal area. The vegetation TOC (kg ha-1) showed the order of the game reserve > ranch > communal area and the trend was similar in both seasons. In summer, the game reserve had the greatest (P < 0.001) TN (kg ha-1) followed by the ranch and the lowest in the communal area, but in winter the game reserve and ranch had similar and higher (P < 0.001) TN (kg ha-1) than the communal areas. In summer, both the game reserve and ranch recorded greater (P < 0.001) herbaceous δ13C and lowest δ15N than the communal area, but in winter, the game reserve had higher (P < 0.001) δ13C than the ranch, though both the game reserve and ranch had similar (P > 0.001) δ15N values. In summer, both the communal and ranch had slightly higher (P < 0.001) woody foliar δ13C than the game reserve, but in winter the ranch had greater (P < 0.001) δ13C than game reserve and communal areas. Woody foliar samples harvested from the ranch showed variations (P < 0.05) in δ15N between seasons being higher (P < 0.001) in summer than winter. The TOC was greatest in summer, in soils collected from the game reserve followed by the ranch and least in the communal land, but in winter, the lowest TOC was recorded in soils collected from the ranch. The soil C:N ratio varied between land management systems in soils collected during summer only being greater (P < 0.001) in the game and ranch than the communal area. The soil TOC (kg ha-1) and TN (kg ha-1) did not show (P > 0.05) differences between land management systems. Soil δ13C level was remarkably (P < 0.05) affected by land management systems, but did not interact with seasons. In both seasons, the communal land had slightly higher (P < 0.001) δ13C level than the other two land management systems. In both seasons, δ15N levels showed great differences (P < 0.001) between land management systems, with highest soil δ15N levels observed in the communal area than the ranch and game reserve. Results on social survey showed that the majority of the interviewed households in Omaandi (63percent), Oshitutuma (53percent) and Epukunoyana (50percent) were female headed families and the remaining were male headed. The mean population of goats and cattle were significantly higher (P < 0.05) in Omaandi and Epukunoyana than in Oshitutuma village, respectively. In this study, household respondents in all villages indicated that all livestock species were primarily kept for wealth status and provision of meat for consumption. Respondents in all villages also indicated that lack of grazing lands and shortage of feed were the primary constraints of livestock production followed by water scarcity and recurring droughts. Elder respondents in all villages perceived overgrazing and climate change as the primary cause of rangeland degradation. Elder interviewees in Omaandi and Oshitutuma villages regarded low grass cover and dominance of poor quality grass (Epukunoyana only) as the primary vegetation indicators of rangeland degradation. The animal related indicators such as stunted animal body as a result of mineral deficiency, high livestock mortality, emaciated body and animals traveling long distance for grazing and water (Oshitutuma only) were regarded in all villages as the primary livestock related indicators of rangeland degradation. Elders from Epukunoyana village ranked low rainfall, high soil and atmospheric temperatures as the primary climate related indicators of rangeland degradation, although in Omaandi and Oshitutuma, high soil and atmospheric temperatures were considered as the primary climate related indicators of rangeland degradation. Based on the findings, this study concludes that land management systems had great influences on the distribution and production of herbaceous and woody vegetation in summer and winter seasons. This study also observed that land management systems interacted strongly with season to influence most vegetation and soil variables. Lastly, based on the study findings, the study concludes that all three communal rangelands are degraded and degradation led to a gradual declining trend in the livestock population over the past 10 to 20 years in the communal areas as a result of feed shortage.]]> Thu 13 May 2021 06:09:07 SAST ]]> Petrogenesis and metallogenesis of the Panzhihua Fe-Ti oxide ore-bearing mafic layered intrusion, SW China https://vital.seals.ac.za/vital/access/manager/Repository/vital:4915 2 wt %) crystallise Fe-Ti oxides early whereas low H2O magmas (< 1 wt %) crystallise oxides late. Early pulses of H2O-poor magma crystallise a sequence of plag+cpx+Fe-Ti oxide (±ol). Later pulses of H2Orich magma subsequently intrude the partially crystallised cumulate sequence incorporating and consuming previously crystallised silicates with subsequent early crystallisation of Ti-magnetite and formation of ore layers. H2O-rich magmas likely have suspended Ti-magnetite microphenocrysts as well, which crystallise at depth in the plumbing system. This model can account for the various characteristic features of the Fe-Ti oxide ore layers at the Panzhihua intrusion as well as other Fe-Ti oxide ore bearing intrusions in the region.]]> Thu 13 May 2021 03:57:26 SAST ]]> Effect of post-slaughter handling on physico-chemical and microbiological quality of red meat along the distribution chain in the Eastern Cape Province, South Africa https://vital.seals.ac.za/vital/access/manager/Repository/vital:27875 Thu 13 May 2021 03:09:14 SAST ]]> Ties that bind https://vital.seals.ac.za/vital/access/manager/Repository/vital:20988 Thu 13 May 2021 00:08:38 SAST ]]>